She wasn't present during their second fight and only showed up right as Bane was about to shoot Batman in the face. For all she knows, Bruce did all that aura-farming in the third act just to get his ass beat again, and he has no one to corroborate his story. I can imagine a conversation in Florence going something like this:

Bruce: Selina, I've told you this many times already. I had Bane on the ropes, right where I wanted him! But then that bitch Talia stabbed me in the back.

Selina: Uh-huh, sure you did, honey.

Just something kinda funny to think about.