Originally Posted by JackWhite
BB and TDK Bruce didn't have anything to prove to himself, or anyone. In TDKR Bruce is in a real bad state of mine and body. Not only does he have the need for a purpose in his life, which to him is being Batman, but he also feels Alfred doesn't believe he can do it anymore. Bruce feeling he had nothing to live for didn't help his case either.
Ah, that answer is so true, and it's a sad one. It makes that scene more emotional.