Is it normal for a friend not to trust you?

I have this best friend who I trust with just about anything. I used to uphold the macho stereotype male friendships are supposed to be when I was around him, but realized I trusted him to the point I didn't need to.

When we hang out, I can tell he trusts me, but he still upholds the stereotypes sometimes. Then at others he breaks them, but if you break them or joke with him about breaking them he gets extremely defensive.

I think he knows he can trust me enough to not need to act macho all the time, but I'm not really sure. It's kind of making our friendship awkward since I can tell there's things he wants to say but won't. I remember how much I struggled with it before I started being honest with him, and it sucked. 3 weeks of hell only to realize he was fine with it and all my assumptions were wrong. Any advice on how I can help him out without pushing him away?