OK. To fully examine Bruce's state in Batman Returns, we must look at who he is in Batman. In the beginning of the film, Bruce hosts a large casino night for charity in his mansion. There could be hundreds of people there, including big figures in Gotham City: Harvey Dent, Commissioner Gordon, the mayor. Bruce is very gracious; six more cases of champagne and you know Bruce Wayne doesn't buy the cheap stuff, along with allowing some reporter he just met a grant to have anything in the house. He even has a seat as a guest of honor at a Harvey Dent press conference. Bruce is outgoing, inviting, and generous. Fast forward through his revelation that the murderer of his parents is the man terrorizing Gotham. This sends Batman on his first (to be fair, known) killing spree. He's using machine guns, rockets, throws a man down a bell tower, and sends the Joker down to his death.
In Batman Returns, there's no gala, no rubbing elbows with Gotham's rich. No one in his home but he and Alfred. His introduction in Batman Returns portrays Bruce as a man who does nothing but be Batman. He sits and waits and when that signal shines bright through his window, he leaps out of his chair because finally he can do something he finds worthwhile. In his first action scene, he commits (attempted?) murder by arson and doesn't make any real reaction to it. That's really unsettling for a character who is traditionally portrayed as a heroic individual.
When he meets Shreck at the end, he says, "Shut up, you're going to jail." When has this Batman ever cared about sending criminals to jail? He has beaten and killed so many men freely to this point; simple goons of the Joker and the Penguin. Shreck is a man who opposed Bruce Wayne directly and allied himself with a monster bent on killing children. He's got an opportunity to kill Shreck, but he doesn't. Batman's blood lust has ceased.
Through his interactions with Selina and coming to know who she is at night, he changes. He invites her to his cavernous home, symbolic of him letting down his many walls that he has built up within himself and has reinforced by the time of the events of Batman Returns. He wants her there when it is clear he hasn't wanted anything out of life other than to be Batman for some time now. During their final scene together, Bruce begs Selina to come home with him so that they can fill in the massive holes in each others' hearts. "We're the same." Bruce finally looks forward to a future that doesn't revolve around Batman. She rejects their possible courtship and their final moment together is coupled with an explosion, a scene directly lifted from Bride of Frankenstein.
The final scene of the film, Bruce is sitting in the back of the car with Alfred driving at night. He left Batman back in his cave. He is visually upset over the disappearance and possible death of Selina, but we know that he is better off now than he was at the beginning of the film. Selina reminded Bruce of the humanity in him and showed how that fragile humanity in the two of them can be lost so easily. If he cannot have her, then she will serve as a reminder of what happens when you drown in the waters of vengeance.
I know am not alone when I say that I think Batman Returns has some beautiful things going on in it. I find it insulting to the film and to myself as a fan for someone to discredit and disregard those elements entirely. You say there is no plot? Yes there is. You just don't have the luxury of Michael Caine explaining it all. If you don't like Batman Returns, that's fine, but don't come into this thread made for us fans just to slander it.