I agree with the people who said ..he only wanted you because he couldn't have you.
Many guys are like this. He wasn't attracted to you, he was attracted to the fantasy of you. He wanted to be with you because it was so beautiful thinking of someone he thought he could never get. I know a guy..he's always like this: whenever I ignore him or be cold on MSN (not on purpose, I was just busier), he would start writing a lot, even writing emails to me. But when I reply with a long email or start replying on MSN really frequently, he would ignore me then say "sorry, I was playing a computer game, I gotta go now, chat next time"