I can't do it anymore

So, like last week sometime.. Well I guess I should introduce myself and all. I'm Kodi, I'm 23 currently and I live in Louisiana for right now. I have a boyfriend, Patrick and we live with my parents. Life isn't so great right now. Pat and I have been together for about 3 1/2 years now. Things aren't going so great.
Last week when Pat and I got back from vacation, he was checking his email on myspace and he got up to help my dad with something and I pushed remember for his myspace for his password. I read an email of his with this chick that he went to school with. She says she doesnt have something for him, but she does. It's not hard to tell. So in this email, He told her that I yell and I nag and I have jealousy issues, which I guess are all true. But he told her that he hides his myspace friends from me because he doesn't want me to flip. He told her that he wanted to go out with her and her friends and go home with some of them. Also he informed her that he was going to ask out one of my good friends when we move back to Kansas. He also told her that if we move anywhere other than back to Kansas, that he was going to leave me. During all this like, my heart was going crazy. I stormed past him into my bathroom, he followed me of course. I was screaming and crying. I knew like, our relationship wasn't the best, but damnit, I love him so much, I can't imagine living my life without him. He means so much to me and we've been through so much.
So we talked for a while. He said that he was sorry and that he felt like our relationship was going down the tube and he didn't know what to do. He doesn't even talk to me about anything. This is ridiculous, how can you tell someone that you want to marry them, but refuse to talk to them about anything? It doesn't make sense to me. I just feel helpless. I don't know whether to believe him that he won't do this again and that he whole heartedly wants to work on our relationship. Or do I just forget it?
He works out on oil rigs, he is gone for months at a time and during this time, I don't feel like he really even cares when we talk on the phone. He sounds like I've bothered him and he'd rather be doing other things. I don't think that is what is happening, but I just don't want to get screwed over again, I've been cheated on and left so many darn times, it's ridiculous. I just want to find the man I'm going to marry and have kids and have my career. I'm tired of dealing with this. I just want this to work out and I'm not sure that it is.
Anyway,
I'm out Peace
K