Let me preface this by saying that I'm not a girl, so feel free to ignore my advice :)
We all have free will, and you have every right to ask her to wait for you... but I still don't think it's right. I think the appropriate, and fair, thing to do is to make your feelings known to her. Let her know how strong your feelings are, and that you hope that you'll have the opportunity to further pursue this relationship when you get home. Asking her to wait, however, is just selfish and cruel. Asking her to not date other people, to not experience the life that all young adults should go through, just because it will make you feel better... If you love her, and really care about her happiness and well-being, I don't know how you could do that.
I'm guessing that deep down you're hoping that she'll offer to wait for you, and save you from having to make this decision. Well, if she does ask, then there's nothing to worry about... because you have to tell her no. Again, if you really love her and care about her happiness, you have to tell her that you're not expecting her to wait. That she can date, fall in love, and get married, without any obligation or guilt toward you.
If you get home and she's single and you're both still feeling the same, great. But I wouldn't count on it.
If I'm coming off as cynical and mean... that's probably because I am :) So why stop now?
Now I'm going to tell you more things that you a) don't want to hear, b) really, really need to hear, and c) probably won't understand until you're much older and more experienced. There is no such thing as "The love of my life". There is no one person out there destined to be your mythical "soul mate". I'm sure you think that what you have for her is so unique, and strong, and special, that no one could ever really understand because you can't even put words to that... Well, nearly everyone here has had that. Several times. I'm very happily married for 7 years now, to the fifth "love of my life". It's funny, because when I think back to #1 and #2(The designation of #2 is soooooo fitting for her, but we won't get in to that!), I can't imagine how I could ever have been as happy as I am now.
Your focus needs to be on your mission, not on this girl.