In Salinger's The Catcher in the Rye, what hard choice does Holden Caulfield have to make, and how does it affect him and others?

The hard choice that Holden Caulfield is faced with in the novel concerns his decision to run away from home in order to avoid entering the competitive world of adults or remain with his family to receive much-needed psychiatric help. Shortly after flunking out of his third prep school, Holden decides that he will sneak back home, visit his younger sister, Phoebe, and run away to somewhere in the country, where he can be by himself and avoid "phonies." Holden is depicted as a traumatized, neurotic teenager, who is struggling with the transformation from adolescence to adulthood. Holden desperately wishes to avoid entering the world of competitive, phony adults and wants to remain young. During an enlightening conversation with Phoebe, Holden mentions that he would like to become a catcher in the rye to prevent children from growing up and becoming adults.
If Holden decides to run away, his family would be devastated by the loss of their second son and more than likely inform the authorities, which would further complicate Holden's relationship with them. Phoebe and D. B. would also be extremely concerned about their brother if he were to run away. As a naive teenager, Holden would endanger his life and well-being by completely abandoning his support base in favor of living in the wilderness alone. Eventually, Holden is influenced by his sister and decides to not run away from home. He is then taken to a mental hospital or sanatorium in California, where he is psychologically evaluated. It is uncertain if Holden ever recovers from his mental instability, but there is hope that he will receive the treatment he needs in California.

In Salinger's The Catcher in the Rye, the hard choice that Holden has to make is whether to grow up and face adulthood or not. This also includes the choice to face his parents after being dismissed from his third private high school or to run away. If Holden stays to face the consequences of his actions, then his parents may be able to get him the help he needs to face adulthood. If, however, Holden chooses to run away, he will only perpetuate his fear of adulthood and possibly keep running for the rest of his life. In addition, Holden and his family members will all experience the consequences of whatever he decides. For example, his parents and siblings will mourn the loss of another brother if Holden disappears from their lives, especially after experiencing Allie's death a few years previously.
The one who might suffer the most by Holden running away is his little sister, Phoebe. In fact, she packs a suitcase with plans to run away with him! Once Holden realizes that Phoebe won't go home without him, he changes his mind about running away and says the following:

"'I'm not going away anywhere. I changed my mind. So stop crying and shut up,' I said. The funny part was, she wasn't even crying when I said that. I said it anyway, though. 'C'mon, now. I'll walk you back to school. C'mon, now. You'll be late'" (207).

The above passage shows Holden actually making the decision to stay for Phoebe's sake. He makes a very adult-like decision by placing his own desires and fears aside for his little sister. This is the first step that Holden takes towards adulthood. As a result, Phoebe stops crying and Holden takes her to the zoo and for a carousel ride. Eventually, Holden receives the help he needs by checking into a hospital near his older brother in California, and the family doesn't have to suffer a life of estrangement from Holden.