Resolved Question

on my fiance one night at a party, since then everything is different. I have pushed myself away from him because I feel like he deserves better than me. He is such a great guy and he deserves so much better. Anyways, during all of this I came into contact with an ex from middle school, we started talking again and realized there was still something there, see the thing is we never actually broke up my parents just moved us away when I finished 9th grade then he moved to Missouri and we just lost contact. I actually moved to Indiana for a month and tried to have a relationship with him, but it didn't work neither of us had anything jobs, place to live,money so i decided to come back to my fiance in Oklahoma where I don't have to worry about things. Why is it that I can't stop thinking about the other guy? I love both of them and i dont know what to do... Can anyone help?

Cheating isn't the end of the world. What seems more important is not that you cheated once, but how you felt aferwards... which is a) more distant from him and b) closer to another person outside the relationship.
Your fiancee deserves to know that you are not emotionally committed to the idea of marriage. Then he can make a choice, at the moment you are denying him the right to be make an important choice about his life.

And finally, this may simply be a grammar error, or it may have more meaning... I note that you write "I *was* engaged..." rather than "I *have been* engaged..." - almost as if you don't regard yourself as engaged any more?