hey man, i have the same problem. but never danced with her. i son't think it's a sin. i think that it's normal for guys to feel this way around girls.
i think a grat time would be around the end of your college carrer. when you ready to start life on your own, it would be great to have someone on your side!
i really don't see anything wrong, especially if they're in thier 20's/ 15, i can see why they would go crazy, but a little coffie isn't that much of a big deal to me.