Is it normal that i think about you everyday but barely knew you?

Is it normal to think about someone almost everyday that you never really knew and haven't talked to in almost 2 years?
I met this boy through friends when I was 16 (I am 18 now) I hung out with him with our friends throughout that whole summer, going to every one of his shows, he was in a band. I had met him because I was talking to one of his bestfriends. I automatically stopped and wanted to talk to him right when I saw him. At one point I had told him I liked him and he had said he had liked me too. It never went anywhere even though we still hung out. It's been almost two years, I facebook stalk him. We don't talk, I say hi sometimes and that's only as far as it ever gets. I can't go a day without thinking about him, he has a girl friend of 15 months. I have a boyfriend of 13 months that would easily come in second to him. I don't know why I'm like this! I feel crazy!