What to do?

I'm in love with my friend and he has no idea. We started talking about two years ago online, but decided that we'd be better off as friends. Lately, I've been seeing him as more than just a friend. Everyday I think to myself, should I smile because we're friend or cry because that's all we'll ever be? He thinks of me as good friend and confides in me about the guys he dates and likes, which absolutely kills me. I don't know what to do. Any advice/help would be appreciated.