How can I stop myself from missing an ex that was a jerk?

I feel like an idiot for even letting this bother me. A few years ago, I was 16 at the time, I dated this guy. I was happier than I have ever been in my life. He made me feel complete. It ended up not working out and ever since, I can't stop hating myself, blaming myself, and it ruins everything. I loved this guy (part of what bothers me is that I know I was 16, so it's stupid) but looking back we had a lot of problems. I'm a feisty one, I like to have fun. He always told me to calm down. Eventually, I got to the point where I was calm all the time just because I thought that was what he wanted and I wanted him to be happy. It wasn't just that though, he changed a lot of things I did. Eventually, he didn't like what happened to me, so he ended it. After he broke up with me, he told people that I was an "abusive controlling b*tch" to make sure I wouldn't get another boyfriend, but he had got another girlfriend after 4 days. Now, I'm smart enough to realize that this guy was a worthless jerk, but I still can't help but have that feeling where I miss him, want him back, and I can't even date any other guys without feeling worthless and like I'm betraying him. I literally get sick to my stomach. It's so dumb, because I really hate him, and we dated for over a year when we were 15/16 so it was stupid kid crap. We broke up a few years ago, and part of me still feels like I miss him, and still would rather be alone than have anyone but him. I've tried everything to get rid of those feelings, but I just can't. I'm disgusted with myself for feeling this way. I'm disgusted with myself for the things I've done to myself because of it. I'm a very emotionally closed person. I don't talk about anything! But, here I am, spilling my guts over the internet like some damn school girl. Can someone please offer me some advice and hopefully a way to end this? Hell, I'd settle for either one.