How Do I get over this JERK of a Guy?

I used to be going out with this amazing guy for about three months, but it ended about three weeks ago. At first I was completely distraught. I did all sorts of RIDICULOUS things to try and get him back and to get him to talk to me. He broke up with me so sweetly, but then didn't talk to me. Ever again. I don't think I could ever go out with him again, and I already have an (almost) boyfriend. But every time I think of him or look at him I get a twinge in my stomach. I honestly don't think I like him anymore, but I don't know why I feel this way. What should I do?