I might feel more charitable towards how nice Bruce appears to be being in that page if he wasn't being such a complete and unmitigated bastard to everyone who cares about him in the same arc. He's asking to be left alone, and in doing so being both a jerk, and completely and unutterably WRONG in his approach.
Maybe it's me, but there's a definite underlying notion that he's being nice to Cass solely in order to have emotional blackmail on his side when he asks her not to help him