cat123

I would suggest a change in your strategy.  
One thing that this world unfortunately lies to young women about is that they can have it all, school, job, career, love, etc.  Except this is a fairy tale and not reality.  Why?  Because as you are finding out, women don't have as much time as men to get things together IF they want to have children.  High risk pregnancies start age 35, plus the increase in birth defects.  If you get married at 30, space kids out 2 years apart + a little bit of solo time at the beginning you are looking at max 2 kids before things get problematic.  This is true because they don't take donor eggs after age 30 for example and the longer a woman waits the harder it is to actually conceive.
So what do women do-unfortunately, the same thing you did which is have one or two serious long-term relationships.  Why be in a relationship for 5 years?  That is way, way too long without a marriage commitment. In addition, that is quite honestly a long time to be in a relationship without sexual relations.  I'm not saying you've had them; just that most relationships do not last that long without sexual relations.  Most men aren't going to be in a long-term relationship like that without sex.  If the woman says no to sex-the man has a choice, either marry her or move on.  For a man to be in a non-sexual serious relationship for 5 years . . . quite honestly I can't imagine a single man being in that type of a non-sexual relationship.  That does not compute with from what you've said is an abusive relationship.
So you were in a 5-year relationship + 1 year off, that's 6 years. So you basically wasted half a decade on one man.  That's not his fault-that's yours, and the fault of a bad culture teaching bad values.  You shouldn't be in a relationship longer than year without really good understanding of whether that relationship is going to end up in marriage or not.  If you figure a year for a serious relationship, a few months of fudge room on either side-you are looking at having a max of 7-8 serious relationships prior to age 30, and that's if everything goes right.  More likely than not, you are looking at maybe 4-5 serious relationships prior to age 30.  This is because some should fizzle out in 2-3 months, but you might have several short relationships in between the serious ones.
That said, the past is the past-all you can really do is learn from it and not repeat the same mistakes again.  That's why I suggest a change in strategy.  What change?  Well first I'd suggest be more active in the process.  Active in identifying what are the main qualifications that you want in a husband. Prioritize you list and be specific.  If you want him to be a romantic-then write down what things would qualify a man for being a romantic (roses, poems, singing, etc.).  If you want him to be a good provider-then write down things that would qualify him as being a good provider.  This might be, "I want him to have a good job in these fields, I want him to be out of school and employed".  If you want him to be a good father, then write down how you will know he would be a good father.  This might be "I want to see him interact with younger siblings, or children".
You need to IDENTIFY specific traits and qualities that you can measure concretely. As in, I know he will be a good father because I've seen him interact with younger siblings and he enjoys roughhousing with them.  Rather than just having this fluffy "I love him", you need to know exactly why you do-and you can identify those things b/c love is action.  It's easy to say the words "I love you/him/her", but unless it's backed up by something concrete it's just words which have no real meaning.
If you have a concrete idea of what it means to be a good husband, what it means to be a good father, what it means to be a good provider, then it becomes very easy to discriminate and you won't get trapped into a 5-year long relationship which blows half you dating lifespan!
On the opposite end of things, why would your dream guy want to even marry you?  What qualities and characteristics do you bring to the table? How can you help HIM in a marriage?  Would you be able to properly care for newborns and teach them the Gospel? A mother's influence on her children cannot be overstated.  The greatest influence happens until age 5-after that it's largely correcting the mistakes you made as a parent from 0-5! Do you willingly do things you know you shouldn't do?  Do you have strong morals to teach your children well? Do you take care of yourself, physically, mentally, spiritually?
If your dream guy came along, how would you make yourself stand out among all the other women who might want him!  Unfortunately, in today's world too many women give up their chastity in an effort to make themselves stand out to the guy they want . . . and that leads nowhere.
So, change your strategy, identify what you want, identify what your spouse would want in you, change yourself to make it happen and then put yourself in situations where you can find that guy.

The sign is pure propaganda. We don't have signs saying "We love our adulterous brothers". We don't have signs saying "We love our pedophilic brothers and sisters".  All the sign signifies is indoctrination and propaganda that anyone who can't control their thoughts and feelings, that anyone who has unnatural proclivities should be coddled . . .except only a certain special group of individuals. It doesn't apply to anyone else . . .except a special group.
I didn't say you were selling me something. I gave you 2 options.
Figure out who you can not criticize and those are the people who hold the power.

I'm sure it is.  The supreme irony is the topic "the Church opposes anti-conversion therapy", when the entire purpose of the Church is about conversion therapy.

It's ridiculous to call out specific sins and say "we love them".  Why not have a sign that says "We love our children who are druggies", "We love our children who are bullies", "We love our children who are pregnant".
It's pandering to the emotionally weak "woke" individuals who think that the mere profaning of words makes something true. It in effect states that prior to this sign being put up, we didn't love them.  It signifies that only by bloviating meaningless words to pander to the world that we love them.
Until people wake up and realize the absolute stranglehold the LGBTQ+ velvet mafia has on people's thoughts, their ideas, and how they have suppressed the righteous desire to help people overcome their weaknesses, this junk will continue.  This group is sacrosanct-they are the new religion, with their priests, alcoyates and high priests. 
It's why the story about Katie Hill is buried. She is a priestess in the new religion and cannot be touched.  As a people we have traded the One True God for a false god.  Good luck!

So, I'd just like to remind us all of the site rules to which we all agreed, when joining the site. 
https://thirdhour.org/forums/announcement/1-third-hour-forum-rules-please-be-familiar-with-these-rules-before-posting/
Specifically,
 

You cannot be serious.
You have a woman who came into Congress as the first openly bisexual woman who is in a throuple.  This throuple involves a thirty year old woman, a thirty year old man and a 22 year old young lady.  The young lady is a paid employee on the campaign staff of the 30 year old woman.  The older woman is elected to Congress.  She is on the following committees:
House Armed Service Committee,   Subcommittee on Tactical Air & Land Forces, Subcommittee on Seapower and Projection Forces
House Committee on Oversight and Reform (Vice Chair) ,Subcommittee on Environment, Subcommittee on Economic and Consumer Policy
House Science, Space, and Technology Committee,  Subcommittee on Space and Aeronautics
Due to her position of influence she has access to classified information.  She is held up as a banner of LGBTQ+ individuals and yet she is openly having sexual relations (or put into compromising situations) with a) an EMPLOYEE!!! b) a young women.
If it were she were a straight male, this would be a massive news story, plastered all over the news about #metoo. 
But b/c she is LGBTQ+, you get comments like the above (basically amounts to a yeah, so what).
Do we have ANY morals anymore in this country?

You cannot be serious.
You have a woman who came into Congress as the first openly bisexual woman who is in a throuple.  This throuple involves a thirty year old woman, a thirty year old man and a 22 year old young lady.  The young lady is a paid employee on the campaign staff of the 30 year old woman.  The older woman is elected to Congress.  She is on the following committees:
House Armed Service Committee,   Subcommittee on Tactical Air & Land Forces, Subcommittee on Seapower and Projection Forces
House Committee on Oversight and Reform (Vice Chair) ,Subcommittee on Environment, Subcommittee on Economic and Consumer Policy
House Science, Space, and Technology Committee,  Subcommittee on Space and Aeronautics
Due to her position of influence she has access to classified information.  She is held up as a banner of LGBTQ+ individuals and yet she is openly having sexual relations (or put into compromising situations) with a) an EMPLOYEE!!! b) a young women.
If it were she were a straight male, this would be a massive news story, plastered all over the news about #metoo. 
But b/c she is LGBTQ+, you get comments like the above (basically amounts to a yeah, so what).
Do we have ANY morals anymore in this country?

I am also very sad Cat123 about the general wickedness of the general population in America.  God's judgments will come on this nation and especially the wicked unless they repent and turn with their whole hearts to God.  We are seeing a corrupting rot especially in the Federal government and some state governments that is spreading because of our sins. 
I pray almost everyday that the Bill of Rights and the United States Constitution will be preserved as long as there is a band of Christians that possesses this land.

It doesn't surprise me in the least bit that she gets to the top of the female hierarchy pretty quickly. In general, women's hierarchy is dominated by who can get the guys and who can be the most emotionally manipulative.  As much an outrageous movie "Mean Girls" is-there is a whole heck of a lot of truth in it when it comes to female hierarchy.
If you are in her country, well that is no bueno-especially if you don't know the culture very well.  It's possible (but IMO highly unlikely) that her behavior is more typical for that culture. I think it highly unlikely, however some culture are much more affectionate than US culture-i.e. they give hugs and kisses (on each side of the cheek).  Some cultures it is seen as no big deal for a married man to give a female friend a hug and a kiss on her cheek.  That is a serious no-no in US culture.  That's where you have to find someone you can trust in that culture-a good Bishop maybe-and simply straight up ask, my wife is doing xyz is this behavior is typical for your culture?  More likely than not, it's not appropriate.  And from what you stated I'm 99.9% sure it's not . . .but it's always good to run that to ground.
From what I've gathered the Plan B or abortion pill is not a pleasant experience and so if your gut is telling you something was off about more likely than not it was. The thing you have to do with your gut is to analyze it and tear down why exactly it is that you have those gut feelings and when you do (which it sounds like you've done a good bit of that) you can build up evidence to support or disprove your gut . . . .most likely your gut is right.
Why are you ashamed for her behavior? If she is sleeping and whoring around-that reflects on her not on you.
There is an absolutely fabulous scene in "Gone with the Wind"-long movie but excellent. Well Ms. Scarlett has married Rhett Butler but secretly still wants to be with another man, Ashley-who is married. She is at Ashley's place of work and they either kiss or hug tightly and other relatives see them.   Word gets back to Rhett and Ashley's wife (who is Scarlett's best friend).  That evening was a birthday party for Ashley.'s wife.  So what to do, what to do. Rhett is being cuckholded.  Scarlett doesn't want to go to the party.  Well Rhett tells her, yes you are going and you are going to wear this dress (which happens to be a very sensuous red dress), and you are going ALONE!  Basically, Rhett refuses to take responsibility for Scarlet's bad behavior and forces her to face the music-it's a great scene.
Nope, I'm a dude married ~15 years myself.  Just been through enough and a lot that I had to face my own music in my own marriage (thankfully nothing with infidelity) many moons ago.  I sort of self red-pilled.  I've never gone to those websites/forums, but I'm familiar enough with their arguments and there is a whole litany of reasons as to why this is a fairly typical problem now. I've gone from an absolutely horrific, horrible get me out of here marriage to a pretty peaceful one.  It's taken work on both our parts.  So I know it's possible. Seeing what marriage can be and it can be quite wonderful-I really do feel sorry for all the MGTOW, incels, etc. that have such distaste and dislike for women. I more have distaste/dislike for the cultural system which has given rise to our current situation.
Some general bits of advice that I've learned.
1) Don't shoulder other individuals responsibilities. Everyone needs help from time to time, but you have to know when to let others lie in the bed they made so to speak. Don't make excuses for other's bad behavior. Each person is responsible for their own feelings, their own actions, their own behaviors.
2) You both have to be extremely stubborn, as in we are both stubborn enough in the concept of this marriage working that we WILL make it work one way or another!
3) You have to actually be married to each other, being a husband and being a wife is a role that you play and those roles (husband/wife) should be the 1st roles you play, above mother/father, above provider/breadwinner/homemaker. And being married is much, much more than a stupid piece of paper signed by some stupid "official".
4) The best place for advice on how to be married is found in the Scriptures.  Genesis, Moses, Abraham, Ephesians, 1 Corinthians, 1 Timothy and Proverbs.  You will NEVER find better marriage advice than what is found in the Word of God. When you study the scriptures, specifically the parts that describe relationships between men and women God WILL enlighten your mind and give you understanding about how to approach things.
Some ancillary things that have helped me better understand people, relationships, etc.  I really do like listening to Stefan Molyneux's podcasts when he talks to people about their problems.  Those shows are generally about 2 hours, but you will learn quite a bit in those two hours of listening, and you come away from it thinking "well at least I don't have that guy's problems!!!!!!"
I've been through a lot in my life and come out on the other side-so if you need more specific help feel free to PM me.

Some comments based on your feedback.  I was pretty accurate about her looks and probably the reason why she married you-i.e. she saw you as the safe, stable provider who to provide protection and resources for her while she had kids.  You are 55 and she is 40, been married 15 years so when you go married she was 25 and you 40.  Now here's another thing think about.
Why is it that she didn't marry some other guy who was in his 30s?  She must have been quite the looker at 25, meaning she could have grabbed guys who were stable in their upper 20s to lower 30s?  Most men are able to be good providers by the time they are late 20s early 30s . . .so why did she go 15 years her senior?  At 25, she's not completely inexperienced in the world-probably graduated college, been in the workforce, possibly mission. So why go 15+ years . . .especially if she is a looker. 
I believe you gave a hint as to why in the above.  My guess is because the men just a little older were either already gone (as in already married) OR rejected her.  Why would a 30-35 year old man reject a 25 year old really good looking woman?  You said it in the paragraph above-but not in the words I'm going to use. 
Emotional maturity.
She uses threats, she is able to control the conversation, control the tone, the emotional setting, the emotional blackmailing of divorce, etc. For someone who is 40, she is extremely emotionally immature. My guess is she probably met a few guys closer to her age, but they recognized her emotional immaturity and said, nah pass.  That's why she is going with younger men-she is extremely emotional immature and used her good looks and her threats of leaving you hanging over your head for the past 15 years.  It's probably why you were never able to stand up to her (nor help her develop emotional maturity).  You felt so blessed to have married her, to be so lucky to marry this great looking gal that you overlooked and ignored her emotional immaturity for so long.
So now the question is what do you do about it. She is an emotionally immature adult at 40 and that's a hard thing to deal with. How do you deal with an emotionally immature adult? She is not a child, however there are lessons that can be learned from dealing with children.  Children are by nature emotionally immature. They throw tantrums over the smallest things, one minute they are happy, the next minute sad.  Tell a child no that hasn't learned to hear no and they melt-down. 
The best way to deal with a child is to not get sucked into their drama. The best way to deal with an emotionally immature adult is the same thing-don't get sucked into their drama. Don't get emotionally involved in the discussion.  Stop worrying about divorce and stop letting that emotional blackmail determine what you are going to do. Be prepared that she might just as well divorce you (so prepare financially), however you can't step up and be the leader she needs if you are worried about it or letting it affect your decisions.
Like I said, you've got to develop boundaries.  If she starts emotional manipulation and talking about divorce-just tell her calmly but firmly "I won't entertain discussions about divorce, this conversation is over"  Mean it and walk away.  If you need to just leave the house until she calms down do so. She is testing you when she brings up divorce and uses it as a weapon . . .as in "is divorce an actual possibility or not?" You have to be the leader and shut it down. You have to be a leader and be absolutely clear about when exactly you would divorce her.  Would you divorce her if she was promiscuous?  If possible, then be blunt and say when she brings up divorce "The only time I would ever entertain divorce is if you have screwed around with another man, otherwise this conversation is over".  You've let her know exactly where the line stands that if she is trying to get you to divorce her, she knows what she needs to do in order to make that happen.
If she starts in with wild mood swings when she doesn't get what she wants, be clear firm and use as few words as possible.  "I'm not going to engage in a conversation like this" or "when you are calm then we can talk" and leave, walk away go take a drive, go read scriptures, etc. She can learn to control her emotions, she can learn to be more rational and less immature, it is very possible, it's just that she's never been forced to do so.  Because of her looks she has been able to get exactly what she wants through emotionally immature behavior. So start teaching her by example how to do so.
Be a leader to your wife.  She needs to know how to become an emotionally mature adult.  The only way she can do that is by seeing what an emotionally mature adult looks like-i.e. from a leader.  So if you can step up and be emotionally mature-completely ignore her childish tantrums, she will eventually realize that it gets her nothing and eventually she will either learn to be more emotionally mature OR she will decide she will commit adultery so you will divorce her OR she will divorce you just because.
The only way at this point to avoid divorce is for her to become emotionally mature-otherwise it's going to happen one way or another.

15 years of marriage. There is a lot to unpack here. 
The primary reason this is occurring is because you and her did not do the proper work during the previous 15 years.  Just because you have a piece of paper and the ability to copulate without Church discipline does not mean you are married.  Being married is a state of being, not something granted-it is something that is earned by lots of hard, hard work.  This is a common thing in today's society because most people (even inside the Church) don't have a clue what it means to be married.  I don't blame you or her-it's just our culture teaches it wrong.  When you first got married, you probably had kids relatively soon and instead of making your roles primarily as husband and wife your primary roles shifted to mother/father.  When you do that-you stop being married.
The reason why what is occurring now is that as kids get older and each partner starts seeing the light at the end tunnel of being mother/father-they start reseeing their role as husband/wife. Then they start seeing this person who they have seen in the role as "parent" for the last 15 years and they don't recognize them at all as spouse.  I do believe it is reversible-but it takes work on by both.  If you don't nip this in the bud now and take some major corrective action, she will almost certainly divorce you as soon as the kids are gone.
Next,  she is as much to blame here as you are.  Do not let her get off scot-free in this.  More likely than not she put more emphasis and attention to either being a mother/career than she did being a wife. Don't go down the route of saying you are the only one at fault-it takes two to tango, it takes two to make a marriage. You need to stop with the self-deprecating talk (i.e. lazy, "not doing enough right things") those sound like things you've been told to say by your wife as she has complained to you about your faults.  Now, it's certainly possible you are lazy, but unless you are one welfare ... most likely you've been a hard-working provider for your family. Don't buy into the lies that you're lazy or that you're not good enough to keep her interest. 
You certainly have your faults, but your wife absolutely has just as much to blame for your marriage not being good-and don't forget that!
Now the red-pill stuff.  There is some very powerful messages in the red-pill and a whole heck of a lot of truth, unfortunately it is also mixed with some very bad lies too.  I would not ever advocate for flirting with other women not your wife-that is playing with fire. It's against God's law, it plays with your wife and it plays with the other women.  Not good.
Now to your wife.  She must be a very attractive lady, or the younger guys she is flirting with are total losers.  Woman's looks generally start dropping around 30+ and it's the very rare woman who at say 40 is able to flirt with and get serious attention from men in their 20s . . .unless she either has money or is really good looking or the men are total losers who couldn't get a date with a paper-bag.  Now I'm going to go with attractive lady, b/c well if she is looking for love with younger loser men-I'd cut bait and tell her good luck!!! (b/c obviously she isn't too bright).
So b/c she is attractive, you won her over somehow.  Women inherently (and good looking women especially!) know their ability to make a man weak in the knees.  Yet with her beauty, she chose you! Somehow, someway this good looking woman who most men would dream about getting chose you!   That's a really good sign for you. Now the question is why did she chose you?  And the follow-up question are those things that you did to win her over still valuable to her?  People change and so what she once valued 15 years ago in you, she may no longer value, but odds are she does and just needs to be reminded of it.
Finally, for good looking women, they know they can get men to do what they want and that any man will try to please them-yet there are many total loser men out there.  My guess is that in you she saw someone who was stable, dependable, reliable. My guess is you provided her a great environment to raise kids in.  However, you two didn't build a marriage together over 15 years, you simply raised kids. 
So what else probably won her over? Most likely it had to do with confidence, my guess is when you were first dating you were much more confident than you are now. You probably held your head a little higher.  Stop being afraid you are going to lose her-that will kill your confidence, start being confident that you can win her again! Women hate insecure, self-loathing men they instinctively will run away from and reject them.  So how to you be confident?
Start putting your foot down. Stop walking on egg shells.  The reason why red pill marriage tells men to flirt, is two-fold 1) it puts the wife in her place and 2) it gives you self-confidence.  I disagree with the method, but agree on the goals. 
If you catch your wife flirting with other men-don't take it.  Tell her directly "That is unacceptable behavior, I will not tolerate that in my marriage" and then walk away. Start standing up for yourself and be a leader!  Other people (including your wife) are drawn to attracted to people who are good leaders.  Start setting boundaries, enforce them and yes confront head on any potential infidelity.
That and you can give Stefan Molyneaux a call-he does call-in shows about this sort of thing, will talk to you for 2+ hours and does a good job.
 

It doesn't surprise me in the least bit that she gets to the top of the female hierarchy pretty quickly. In general, women's hierarchy is dominated by who can get the guys and who can be the most emotionally manipulative.  As much an outrageous movie "Mean Girls" is-there is a whole heck of a lot of truth in it when it comes to female hierarchy.
If you are in her country, well that is no bueno-especially if you don't know the culture very well.  It's possible (but IMO highly unlikely) that her behavior is more typical for that culture. I think it highly unlikely, however some culture are much more affectionate than US culture-i.e. they give hugs and kisses (on each side of the cheek).  Some cultures it is seen as no big deal for a married man to give a female friend a hug and a kiss on her cheek.  That is a serious no-no in US culture.  That's where you have to find someone you can trust in that culture-a good Bishop maybe-and simply straight up ask, my wife is doing xyz is this behavior is typical for your culture?  More likely than not, it's not appropriate.  And from what you stated I'm 99.9% sure it's not . . .but it's always good to run that to ground.
From what I've gathered the Plan B or abortion pill is not a pleasant experience and so if your gut is telling you something was off about more likely than not it was. The thing you have to do with your gut is to analyze it and tear down why exactly it is that you have those gut feelings and when you do (which it sounds like you've done a good bit of that) you can build up evidence to support or disprove your gut . . . .most likely your gut is right.
Why are you ashamed for her behavior? If she is sleeping and whoring around-that reflects on her not on you.
There is an absolutely fabulous scene in "Gone with the Wind"-long movie but excellent. Well Ms. Scarlett has married Rhett Butler but secretly still wants to be with another man, Ashley-who is married. She is at Ashley's place of work and they either kiss or hug tightly and other relatives see them.   Word gets back to Rhett and Ashley's wife (who is Scarlett's best friend).  That evening was a birthday party for Ashley.'s wife.  So what to do, what to do. Rhett is being cuckholded.  Scarlett doesn't want to go to the party.  Well Rhett tells her, yes you are going and you are going to wear this dress (which happens to be a very sensuous red dress), and you are going ALONE!  Basically, Rhett refuses to take responsibility for Scarlet's bad behavior and forces her to face the music-it's a great scene.
Nope, I'm a dude married ~15 years myself.  Just been through enough and a lot that I had to face my own music in my own marriage (thankfully nothing with infidelity) many moons ago.  I sort of self red-pilled.  I've never gone to those websites/forums, but I'm familiar enough with their arguments and there is a whole litany of reasons as to why this is a fairly typical problem now. I've gone from an absolutely horrific, horrible get me out of here marriage to a pretty peaceful one.  It's taken work on both our parts.  So I know it's possible. Seeing what marriage can be and it can be quite wonderful-I really do feel sorry for all the MGTOW, incels, etc. that have such distaste and dislike for women. I more have distaste/dislike for the cultural system which has given rise to our current situation.
Some general bits of advice that I've learned.
1) Don't shoulder other individuals responsibilities. Everyone needs help from time to time, but you have to know when to let others lie in the bed they made so to speak. Don't make excuses for other's bad behavior. Each person is responsible for their own feelings, their own actions, their own behaviors.
2) You both have to be extremely stubborn, as in we are both stubborn enough in the concept of this marriage working that we WILL make it work one way or another!
3) You have to actually be married to each other, being a husband and being a wife is a role that you play and those roles (husband/wife) should be the 1st roles you play, above mother/father, above provider/breadwinner/homemaker. And being married is much, much more than a stupid piece of paper signed by some stupid "official".
4) The best place for advice on how to be married is found in the Scriptures.  Genesis, Moses, Abraham, Ephesians, 1 Corinthians, 1 Timothy and Proverbs.  You will NEVER find better marriage advice than what is found in the Word of God. When you study the scriptures, specifically the parts that describe relationships between men and women God WILL enlighten your mind and give you understanding about how to approach things.
Some ancillary things that have helped me better understand people, relationships, etc.  I really do like listening to Stefan Molyneux's podcasts when he talks to people about their problems.  Those shows are generally about 2 hours, but you will learn quite a bit in those two hours of listening, and you come away from it thinking "well at least I don't have that guy's problems!!!!!!"
I've been through a lot in my life and come out on the other side-so if you need more specific help feel free to PM me.

Unfortunately, the problem with emotionally immature individuals is they don't know what they want or what they need.  They have their feelings all mixed up and confuse what they feel they need with what they really need.
I use children, b/c it's easiest to see the pattern with children.  A child feels they need to play video games all night long and when a parent tells them no, they will get all upset and have a big fit.
An emotionally immature adult (in this case a woman) will feel they need "validation" about their looks, their ability to catch a man and will start flirting with other men, another adult tells them no and they get upset and have a big fit.
Someone who is emotionally immature (a child or a adult) has absolutely no concept of what they really need and are only ruled by their emotions instead of allowing emotions to be a part of them-but not ruled by them. For and emotionally immature adult whatever they feel is whatever they need.  For an emotionally mature adult, they recognize that sometimes our feelings mislead us, sometimes you can't get what you want, that while yes it would be great to stay up late doing your favorite thing-you'll pay for it the next day.  Someone who is emotionally immature can't do that. Someone who is emotionally mature recognizes that while it might be fun to go flirt with and have a fantasy relationship with that good looking guy/gal-it doesn't pay and in the long run is extremely detrimental.

Some comments based on your feedback.  I was pretty accurate about her looks and probably the reason why she married you-i.e. she saw you as the safe, stable provider who to provide protection and resources for her while she had kids.  You are 55 and she is 40, been married 15 years so when you go married she was 25 and you 40.  Now here's another thing think about.
Why is it that she didn't marry some other guy who was in his 30s?  She must have been quite the looker at 25, meaning she could have grabbed guys who were stable in their upper 20s to lower 30s?  Most men are able to be good providers by the time they are late 20s early 30s . . .so why did she go 15 years her senior?  At 25, she's not completely inexperienced in the world-probably graduated college, been in the workforce, possibly mission. So why go 15+ years . . .especially if she is a looker. 
I believe you gave a hint as to why in the above.  My guess is because the men just a little older were either already gone (as in already married) OR rejected her.  Why would a 30-35 year old man reject a 25 year old really good looking woman?  You said it in the paragraph above-but not in the words I'm going to use. 
Emotional maturity.
She uses threats, she is able to control the conversation, control the tone, the emotional setting, the emotional blackmailing of divorce, etc. For someone who is 40, she is extremely emotionally immature. My guess is she probably met a few guys closer to her age, but they recognized her emotional immaturity and said, nah pass.  That's why she is going with younger men-she is extremely emotional immature and used her good looks and her threats of leaving you hanging over your head for the past 15 years.  It's probably why you were never able to stand up to her (nor help her develop emotional maturity).  You felt so blessed to have married her, to be so lucky to marry this great looking gal that you overlooked and ignored her emotional immaturity for so long.
So now the question is what do you do about it. She is an emotionally immature adult at 40 and that's a hard thing to deal with. How do you deal with an emotionally immature adult? She is not a child, however there are lessons that can be learned from dealing with children.  Children are by nature emotionally immature. They throw tantrums over the smallest things, one minute they are happy, the next minute sad.  Tell a child no that hasn't learned to hear no and they melt-down. 
The best way to deal with a child is to not get sucked into their drama. The best way to deal with an emotionally immature adult is the same thing-don't get sucked into their drama. Don't get emotionally involved in the discussion.  Stop worrying about divorce and stop letting that emotional blackmail determine what you are going to do. Be prepared that she might just as well divorce you (so prepare financially), however you can't step up and be the leader she needs if you are worried about it or letting it affect your decisions.
Like I said, you've got to develop boundaries.  If she starts emotional manipulation and talking about divorce-just tell her calmly but firmly "I won't entertain discussions about divorce, this conversation is over"  Mean it and walk away.  If you need to just leave the house until she calms down do so. She is testing you when she brings up divorce and uses it as a weapon . . .as in "is divorce an actual possibility or not?" You have to be the leader and shut it down. You have to be a leader and be absolutely clear about when exactly you would divorce her.  Would you divorce her if she was promiscuous?  If possible, then be blunt and say when she brings up divorce "The only time I would ever entertain divorce is if you have screwed around with another man, otherwise this conversation is over".  You've let her know exactly where the line stands that if she is trying to get you to divorce her, she knows what she needs to do in order to make that happen.
If she starts in with wild mood swings when she doesn't get what she wants, be clear firm and use as few words as possible.  "I'm not going to engage in a conversation like this" or "when you are calm then we can talk" and leave, walk away go take a drive, go read scriptures, etc. She can learn to control her emotions, she can learn to be more rational and less immature, it is very possible, it's just that she's never been forced to do so.  Because of her looks she has been able to get exactly what she wants through emotionally immature behavior. So start teaching her by example how to do so.
Be a leader to your wife.  She needs to know how to become an emotionally mature adult.  The only way she can do that is by seeing what an emotionally mature adult looks like-i.e. from a leader.  So if you can step up and be emotionally mature-completely ignore her childish tantrums, she will eventually realize that it gets her nothing and eventually she will either learn to be more emotionally mature OR she will decide she will commit adultery so you will divorce her OR she will divorce you just because.
The only way at this point to avoid divorce is for her to become emotionally mature-otherwise it's going to happen one way or another.

15 years of marriage. There is a lot to unpack here. 
The primary reason this is occurring is because you and her did not do the proper work during the previous 15 years.  Just because you have a piece of paper and the ability to copulate without Church discipline does not mean you are married.  Being married is a state of being, not something granted-it is something that is earned by lots of hard, hard work.  This is a common thing in today's society because most people (even inside the Church) don't have a clue what it means to be married.  I don't blame you or her-it's just our culture teaches it wrong.  When you first got married, you probably had kids relatively soon and instead of making your roles primarily as husband and wife your primary roles shifted to mother/father.  When you do that-you stop being married.
The reason why what is occurring now is that as kids get older and each partner starts seeing the light at the end tunnel of being mother/father-they start reseeing their role as husband/wife. Then they start seeing this person who they have seen in the role as "parent" for the last 15 years and they don't recognize them at all as spouse.  I do believe it is reversible-but it takes work on by both.  If you don't nip this in the bud now and take some major corrective action, she will almost certainly divorce you as soon as the kids are gone.
Next,  she is as much to blame here as you are.  Do not let her get off scot-free in this.  More likely than not she put more emphasis and attention to either being a mother/career than she did being a wife. Don't go down the route of saying you are the only one at fault-it takes two to tango, it takes two to make a marriage. You need to stop with the self-deprecating talk (i.e. lazy, "not doing enough right things") those sound like things you've been told to say by your wife as she has complained to you about your faults.  Now, it's certainly possible you are lazy, but unless you are one welfare ... most likely you've been a hard-working provider for your family. Don't buy into the lies that you're lazy or that you're not good enough to keep her interest. 
You certainly have your faults, but your wife absolutely has just as much to blame for your marriage not being good-and don't forget that!
Now the red-pill stuff.  There is some very powerful messages in the red-pill and a whole heck of a lot of truth, unfortunately it is also mixed with some very bad lies too.  I would not ever advocate for flirting with other women not your wife-that is playing with fire. It's against God's law, it plays with your wife and it plays with the other women.  Not good.
Now to your wife.  She must be a very attractive lady, or the younger guys she is flirting with are total losers.  Woman's looks generally start dropping around 30+ and it's the very rare woman who at say 40 is able to flirt with and get serious attention from men in their 20s . . .unless she either has money or is really good looking or the men are total losers who couldn't get a date with a paper-bag.  Now I'm going to go with attractive lady, b/c well if she is looking for love with younger loser men-I'd cut bait and tell her good luck!!! (b/c obviously she isn't too bright).
So b/c she is attractive, you won her over somehow.  Women inherently (and good looking women especially!) know their ability to make a man weak in the knees.  Yet with her beauty, she chose you! Somehow, someway this good looking woman who most men would dream about getting chose you!   That's a really good sign for you. Now the question is why did she chose you?  And the follow-up question are those things that you did to win her over still valuable to her?  People change and so what she once valued 15 years ago in you, she may no longer value, but odds are she does and just needs to be reminded of it.
Finally, for good looking women, they know they can get men to do what they want and that any man will try to please them-yet there are many total loser men out there.  My guess is that in you she saw someone who was stable, dependable, reliable. My guess is you provided her a great environment to raise kids in.  However, you two didn't build a marriage together over 15 years, you simply raised kids. 
So what else probably won her over? Most likely it had to do with confidence, my guess is when you were first dating you were much more confident than you are now. You probably held your head a little higher.  Stop being afraid you are going to lose her-that will kill your confidence, start being confident that you can win her again! Women hate insecure, self-loathing men they instinctively will run away from and reject them.  So how to you be confident?
Start putting your foot down. Stop walking on egg shells.  The reason why red pill marriage tells men to flirt, is two-fold 1) it puts the wife in her place and 2) it gives you self-confidence.  I disagree with the method, but agree on the goals. 
If you catch your wife flirting with other men-don't take it.  Tell her directly "That is unacceptable behavior, I will not tolerate that in my marriage" and then walk away. Start standing up for yourself and be a leader!  Other people (including your wife) are drawn to attracted to people who are good leaders.  Start setting boundaries, enforce them and yes confront head on any potential infidelity.
That and you can give Stefan Molyneaux a call-he does call-in shows about this sort of thing, will talk to you for 2+ hours and does a good job.