Sally shows up ten minutes late to meet Holden, but looks so good he doesn't hold it against her. He feels like marrying her, even though he doesn't particularly like her. He keeps describing himself as crazy.
Holden's first real attempt to connect with a girl. His emotions fly out of control, and he seems to sense he's losing his grip.
At the play, the actors' performances seem phony and conceited to Holden. During intermission, Sally talks to a boy named George who she knows from Andover. Their phony conversation disgusts Holden.
Anyone who seems self-confident or comfortable in society strikes Holden as phony. He only trusts disdain and skepticism.
After the performance, Holden and Sally go ice-skating. Holden guesses that Sally wanted to go ice-skating just to wear a little skirt and show off her "cute ass," which, he has to admit, looks good.
Holden's conflicted feelings about girls arise again. Even if he's right about Sally, it should flatter him. But he seems to think it makes Sally a threat.
Soon they head inside. As they drink cokes, Holden asks Sally if she gets fed up with stuff like school. Holden then says that he hates school and everything else: taxis, New York, etc. Sally asks him to stop shouting, but Holden continues that he's only in New York because of Sally and would otherwise be off in a cabin in the woods. He says he's in bad shape. Sally readily agrees.
Hating everything and wanting to escape society completely are signs of depression. Sally's request that Holden stop shouting, though, shows that he's past depression —he's out of control. His comment about being in bad shape shows he knows he's on a downward spiral.
Suddenly Holden suggests they should run away to New England and live in a cabin together. Sally tells him there will be time for such things when they're older. Holden tells Sally she's "a royal pain in the ass." Sally starts to cry. Holden apologizes, then starts to laugh, then finally leaves.
Sally reacts realistically to Holden's fantasy of escape from society and adulthood. Sally is playing life by the rules, which drives Holden into a rage.
Holden remarks in retrospect that he wouldn't want to go with Sally on a trip anyway, and concludes that he must be insane.
It's ironic that Holden says he's insane for inviting Sally on the trip, when he's just been screaming at her.