Holden gets drunk at the Wicker Bar. He thinks about calling Jane, but instead calls Sally from a pay phone, and ends up infuriating both Sally and her grandmother.
Jane represents childhood; Sally represents adulthood. Holden tries to have successful adult interactions, but they all fail.
Back in the bar, Holden goes to the bathroom and imagines himself as an actor "concealing the fact that I was a wounded sunuvabitch." He unsuccessfully hits on the lounge singer and the hat-check girl. Finally, he picks up his hat at the hat-check and leaves.
Holden imagines himself hiding the fact that he's a "wounded sunuvabitch." But he's not just imagining it—he actually is "wounded" and is trying to hide it.
Holden walks to Central Park to check on the ducks in the lagoon. During the walk, Holden drops the record he bought for Phoebe and nearly cries. At the park, the lagoon is half frozen and there are no ducks.
The children's record breaks. The ducks adapt and change to survive. Holden can't protect childhood and avoid growing up.
Holden sits on a bench, freezing. He thinks he might catch pneumonia and imagines his own funeral. He then remembers how he missed Allie's funeral because he was still in the hospital from having smashed the garage windows with his bare hands.
Holden connects his own death to Allie's, and it seems likely that Allie's death is the source of Holden's depression. He seems to be still hurt, angry, and suffering.
Holden thinks how awful Phoebe would feel if he died of pneumonia, so he decides to go see her. He knows returning home is risky because he might get caught by his parents, but he suspects they'll be asleep and he'll be able to slip in and out without seeing them.
Holden snaps out of his suicidal fantasy by thinking of the wishes of a child, his sister. It's by thinking of society, rather than himself, that saves him.