Dating can seriously kill a great friendship if it doesn't work out.... I've been one who has been able to maintain a friendship when everything falls apart... but it takes two to make that work.... most people just walk away from each other...
well its ok to hang out , but asking a person out is another diffrent thing entirely. sometimes its ok to just hang out..! Take your time and see where it goes..
could be he doesnt want to get involved with her that way. I find women fascinating to hang around and talk to its hard to hang around them sometimes without them thinking your goal is some sort of romantic involvement or without them ploting to get you into bed somehow women are not really differant than men
The age difference may have something to do with it. He also may just realize that while you two could be fantastic close friends, romance might not be in the cards.
I guess, both of them didn't realised that 'hanging out' is sort of date too!!!