one-sided - SPOILER
It seemed to me the resolution at the end was one-sided.
They both have behaved badly through much of the film, with a sarcastic Bruce Willis carrying on really obnoxious temper tantrums and Michelle Pfeiffer being depressed and rejecting. I kept thinking of that scene in "Radio Days" where the marriage counsellor tells Woody Allen's parents "I think you DESERVE each other." And they reply, "What does THAT mean? We didn't come here to be insulted!"
Outside the restaurant after his screaming meltdown (I kept hoping the manager would throw him out) he has a little glimmer of understanding that he hasn't seen things through her eyes, and he needs to apologize for that, but he takes it back when he sees the orthodontist with her. That's the only concession we see him make.
Then in the final scene suddenly she goes all out in forgiving, apologizing, and accepting, and all he does is stand and smile. Never anything about his own part in their problems.
If this happened in real life, the reconciliation wouldn't have a chance of lasting, because it would need Bruce Willis to come forward with a lot more awareness and self-criticism than he's showing anywhere in the movie.
No wonder a poster here said her husband used to make her watch this ending when he wanted to prove to her that all they needed in their marrige was for her to agree everthing should go his way.