Who knew.....

I never would have guessed that my boyfriend was insecure. I always thought i was the one with confidence problems, a low self esteem, cos honestly i don't think much of myself. And he always came across so confident, big headed and full of himself. A bravado, just an act apparently. It honestly took me by surprise his confession of this, the fact he doesn't understand why I'm with him, cos he isn't really what i would call my type. But i would have no one else, its him an that is it. Which really means something coming from me, cos i used to always see possibilities in other guys, but I have him. I don't need anyone else.
But now I'm trying to show him what i see in him, explain why i think he is so amazing, and he refuses to listen, to see what I see in him.
Guys just never seem to appear so doubtful of themselves, always confident almost cocky, but is that all an act? Are most guys just putting on a show?