I know he likes me,but why is he doing this?

I have been talking to this guy for about 10 months now. During the first couple of months I would talk to him about everything, including all of my guy problems and he would help me through them. He even gave me advice because I liked his friend for awhile, and he told me it was a bad idea, which it was. He asked me to homecoming and prom, but I said no because I didn't go to homecoming and I went to prom with the guy I really liked at the time. In February, I was talking with him in class, and he told me, "Esme, I really like you,and I've liked you for the past four years.", but he had a girlfriend, which he still has now. I told him if he didn't break up with his girlfriend, I couldn't be anything more than friends, because I had started to really like him too. He then told me he would break up with his girlfriend for me. We then went to a gymnastics meet to take pictures for yearbook and he took me and some friends to his house, and we ate some pizza. He took my friends home and I didn't want to be at home by myself, so I asked him if he wanted to go to a park and talk for awhile and he said sure why not. It was really cold, so by the time we got back in his car, he was really cold, because I was wearing a sweater and he wasn't. When we got in the car, he told me his hands were really cold and if I could warm them up, so we held hands, nd we went to Sonic to get specialty drinks. He kept on poking me while he was driving because I'm really ticklish and he loves to hear me laugh. We then left Sonic and we went back to my house and we were just sitting in the car and he kept on poking me and poking me, and I was leaning towards him and I looked at him and he looked at me, and we kissed. My conscience got the best of me, and I realized after about ten seconds we shouldn't have kissed because he was still with his girlfriend. I told him I better go and I hugged him and I went inside. I left the following week but before I left, I felt really guilty for kissing the guy, so I told his girlfriend. When I came back, I was told him and his girlfriend broke up. I felt really bad because I thought I was the reason they broke up, so I completely stopped talking to him. While I wasn't talking to him, he sent me a note and dedicated a song to me. I really liked him, but I didn't want to be a slut,that's what all my friends said I would be if I did go out with him. He went back to his girlfriend after about a month and me and him took another ride to my house, but nothing happened, except him playing the song he dedicated to me. He said every time he hears it, it reminded him of me. I realized I really liked him, and I didn't care what people would say, so I told him that I really liked him. He said he like me so much too, but he didn't want to break his girlfriend's heart over me, again. He's not in town right now, so he sent me a message saying, hi mi amor(my love). I really like this guy but I don't know what to do anymore... Please help! Sorry it's kind of a long story.