I think the thing is that you’ve now been Friends for so long. That once you “Go There”, and it doesn’t work out, that it will Never Be The Same. Also, maybe (depends on the guy) the age difference is freaking him out. After all, when he met his old girlfriend, you were 12! A third thing ~ you’ve been the one (I think) to mostly initiate, to put ideas in his head that weren’t really there before.

He seems passive. I would let him take the lead. Forget the sexual tension. Just see what happens.

But don’t you think he should be your official beau first, who loves you (and says and shows it)?