My crush moved away...

My crush moved to the States about a mês atrás but just came back this week to get the rest of their things. I didn't get to see him, but my best friend did. The last time I saw him was June 20. I don't know his address/phone number... I have no way of contacting him. I really miss him and everytime I start to talk about it, the person I'm talking to changes the subject. Since I probably won't see him again, or for a really long time, I'm trying to forget about him. I think I'm doing pretty good so far, but the occassional thing will set me off. There's also a song that reminds me of him, so I was hoping someone would have some tips on being able to listen to the song without becoming incredibly sad and fogetting about him. Thanks.