My heart is actually broken

I used to be a very happy person. In fact, I was that loud and annoying kid who was always laughing and didn’t care what others thought. I do well in school; I dont really try very hard and I get all A’s. I have friends; they all think I’m the happiest guy alive. At school, I still act happy even now; I don’t want them to know. I have a girlfriend; a beautiful, sexy, funny, silly girlfriend, and I loved and still love her very very much. But on October 1st, 2011, she sent nudies to one of her guy friends. When I found out, I was actually driving for my driving permit with my instructor. I was so… frozen. I had a blank expression and looked like I was about to melt into the seat. All the while the anger and fear and devastation was growing inside of me. All this time I had thought that she was an angel, and that she was perfect and a good girl. She was very religious; in other words, I didn’t expect it at all, and it made it so much worse. I wanted to veer the truck into the opposite lane; I wanted to open the door and jump out into the windshield of an oncoming car. She denied it at first, and after a long while she slowly revealed the truth. She lied. I don’t think I’ve ever cried so hard. I had lost grandparents and I’ve been through breaking up with a 6 month relationship before, but nothing topped the pain I had now. What made it so terrible was that I still loved her; I still do. I gave her a second chance, hoping we’d be better as time went on. It didn’t; I changed. Ever since then our relationship has been so damn rocky; she’s broken up with me twice, hooked up with another guy and gave him a bj, she flirts with all her many guy friends, and everything gets me so down. Shes kissed her guy friends, she has emotionally battered me dead and broken, cold hearted and helpless. What’s worse now is even something so little as her liking a picture of a shirtless guy on facebook will get me on my knees crying; as it brings back all the shit that’s happened and I convince myself I’ll never be enough for her and that she wants someone else and someone better, and she doesn’t love me. But she says she does. And I love her. But whenever I get upset, she gets mad at be and yells and cries and makes me feel terrible for being the person I am. I think about suicide often, and I often will scratch my wrists with my finger nail until I’ll bleeding. I don’t know what to do; all of her friends and her mother hates me because they think I treat her like shit because she writes stuff on Twitter about how horrible I am, and she’s always crying because I’m depressed about something. I dont know what to do, I tried breaking up with her twice in the past month but I cant, because I love her so damn much and I never want to leave her. But I don’t know how much more of this torture I can take, I feel like Dimmesdale with a female leech. I might end up like him too; sometimes I even hope I do. Except I dont think I did anything wrong. I hate my life. It may be better than some other people’s lives I guess, but that doesn’t mean I have to love it. The 7th layer of hell is probably worse than the 6th; that doesn’t mean you gotta love being there.