Why are guys so mean sometimes?

So here's the whole story and I'm ready for some serious advice. I met this guy at a wedding. He wouldn't stop checking me out. Every time I looked over he was staring at me. The next day he found me on myspace and wrote me a message. Of course we started chatting at exchanged numbers. We started dating (my parents didn't approve exactly but tried to be supportive) So there was talk of marriage and we talked about some pretty serious things. One Saturday night I said I was going to bed and he was out partying so I text him goodnight. He said goodnight babe I love you and the next morning he wanted to be done because he met some girl at the bar. I was heart broken. Devastated. Worst break up of my life. Couldn't sleep, eat, barely even breathe. It was horrible. A month later I had started to get my life back together and guess who writes me an e-mail asking if we can be friends again. I took a few days to think about it and decided it would be ok. He found out the girl was a psycho and was getting rid of her. We started talking as friends but then it led to back how we were. Saying i love you and acting like we were together but he never wanted to label it as "boyfriend/girlfriend". This went on from April to about October. Ooh and we lived four hours from each other. I made all the effort in the world to go see him and make time for him. He tried to come see me as much as he could with his car broken. Things were ok but he could be very manipulative. I knew he was talking and flirting with other girls around September. I didn't know what to do because I found out in a way he could never know about. He would always get mad and tell me I was lying if I went out with girls. He's always tell me that i was really hanging out with boys. This one time I found out he'd called psycho girl. He got so mad he literally choked me. All in all he's not a very nice guy. So in October he said he was done and I was kinda happy. I handled it well and was ready to move on. I showed him i didn't care and he told me he was ready to "change" stop drinkin and make his life better. Start to grow up. He's 25 and acts like he's 19. He said he was ready and he'd stopped talking to this new girl (who he's been messing around with the last few months...this is December by this time) and he was ready to be together. Of course me being the idiot I get my hopes up and right before Christmas he deletes me from facebook and says he's done. No to my question......what do i do to get over this guy? Can anyone help me? I know I'm better off but I'm not a super confident girl and it hurts. And I live in a culture where marriage is shoved down young girls throats. I'm a mess hear and need some serious advice. I want to be happy again. He's one of those guys I wish I never would've met! Can someone help me move on? And come good advice on how to get back into meeting people?