[He can't help smiling at her attitude. Sweet as ever. Though, he refrains from commenting on it in that way. The last thing he wants to do is say something flirty. So, what is a normal, friend way of complimenting someone like that?]

I really admire that attitude of yours. Don't worry, I... think I'm getting better in those respects. It isn't constantly on my mind like it used to be.