I don't know what to do anymore

It's funny how you know that what you're doing is stupid and makes no sense and yet you do it anyway...I met a girl through myspace a bit over two years ago, and it was what some more-than-faithful people would call "love at first sight". We had everything in common. Soon enough, I found myself thinking about her as more than just a friend. For a 13 year old girl that had been severely depressed for quite some time, turning bisexual wasn't exactly a good addition to the lot. We ended up "going out" for the first time, and the relationship was great up to the extent where we both thought we were truly in love with each other. We talked every day, we had what we called Cheesy Time, and we weren't dating anybody else in our own states. Then some guy she liked asked her out, and, well. Online relationships are hardly even real, so I went out the window with a couple of insults from her and the promise of never talking to her again. She broke up with him, I spent a whole summer crying over her, and then we got back together. We would always date a month, or a month and a half max. When we broke up that time, she and her friend left me voice mails saying that I should kill myself. That I wasn't worth anything. We sued them for being abusive and racist, but y'all know how those things go. A private investigator ended up taking my computers and my phone, but did nothing to them. After a couple of months without talking to her, we started going out yet again. Outcome: having her break up with me on Valentine's day. We didn't talk for almost four months, until she decided that she did want to talk to me. All this time...I would always tell her that I loved her. That I would do anything for her. That I wanted to marry her, and be with her forever. Stupid, I know. You're basically keeling over one girl that you have never even touched or talked to physically. We were alright for a while. And then yesterday (Valentine's day again, maybe she plans it?) she told me that she didn't want to talk to me anymore. Again. I ended up telling her that we would just stop talking to each other so much, and she agreed, but she said that she never loved me, and that she wouldn't even consider dating me again. I've spent more than two years "loving" this girl. All I feel now is pain. I have random crying outbursts, I started thinking about cutting myself again, I'm having trouble breathing. And she doesn't even care, and it's not like I can tell her. It'll just push her away.

Sorry for making that so long, I just needed to get it out and there's no one around that really listens to what I say. They're just waiting for their turn to speak. So...I don't know what to do. I feel like I can't live without her. I'm going through different problems right now, from school to legal problems, to family problems...I can hardly think anymore. I'm constantly stressed out, my grades are going down, I've given into bulimia and anorexia, and I'm just never good enough for anything. I don't even want to live anymore. I need help. And I'm not getting it from anywhere.