Maybe it isn't relevant in this case, but if you were both into playing music I'd say what matters is, can you play well together? I've known some people it's fun to play with, though they aren't maybe too much fun in between tunes.

In this case it doesn't sound like friendship, more a situation where being friendly isn't too easy. It might be temporary thing with this young man, tying in with some problems he's going.

Have you talked about this with your friend, his mother?