I think it's totally possible. When I lost my virginity at like 14, me and the guy both were young and we weren't in a 'relationship'..mainly just being curious. I've known him since I was like 7 or 8 because our families have all been good friends for a long time. I'm 21 now so that was a long time ago and we're still friends. It doesn't seem weird around him or anything. I guess you could say I forget about having sex with him because I never have really thought back about it until now. Him, his wife, and their kids are actually our neighbors. DH knows about what happened with us, the guys wife also knows...but it's not really an issue for all of us to sit in a room together and have a conversation just like friends.