If you really like him a lot as a friend -- I mean a close friend, not just a "hiya" friend -- and as the kind of friend you trust and respect, you shouldn't turn him down. You should marry him.
Marriages based on strong friendships are the kind that last.
Oh, I agree! Completely! You're very right.
This wasn't that sort of situation at all. Just a friend who I play music with, but who would never, ever, ever be anything more...for lots of reasons I don't want to go into.