Here is the story in a nutshell:
I'm a BYU student with 2 years under my belt and 2.5 years to go. I'm an RM and endowed member. This summer I wasn't at BYU but rather was working at an out of state job that kept me working 7 days a week (meaning no church attendance for the whole length of the summer). During the entire summer I didn't pay tithing either, and slowly stopped reading the Book of Mormon as well. At the same time, I got a girlfriend (one of my co-workers) who is not a member, but basically what others would call a "dry mormon". We hit it off really well, and I very much love her and would love for her to be my wife someday. The only hangup is that I would like to share the gospel with her before that point because it's something important to me and something that I really want to share with the person that might be my lifelong (and hopefully eternal) companion. I honestly can't see myself being with someone else. Here's my difficult situation however: Just before I went back to school (she is remaining out of state, but we will be visiting once a month or more) we had sex. It was entirely consensual and I didn't regret it too much at the time, though I knew it was wrong (I'd say I was more or less spiritually desensitized). As soon as I got back to BYU again however and remembered what it meant to fully live the gospel/felt the spirit here and realized how far I had slipped (and how quickly) I felt (and still feel) very guilty. I'd like to talk to a Bishop because I still love her and want to make things right, and I know I can't honestly share the gospel from my current position but since I broke my temple covenants, it would seem that the most likely punishment would be disfellowshipment (or if more extreme, then excommmunication), either of which I would be willing to work through to come back to full membership. What that means however is that I would lose my ecclesiastical endorsement to BYU and could not come back until the end of my probationary period (if at all). Of that, and of the other potential consequences, I am terrified. I want to make things right, but I can't imagine having school postponed for an entire year (or indefinetely) and how I could possibly sort that out at all. Just looking for some help/advice/motivational support here and thank you for all your comments.