What is Salinger's purpose of having Holden refer to other people and situations in the book as "depressing"?
I feel as though there is a common thread between all of the people and scenarios that Holden calls depressing or a common reason why Holden calls these certain things depressing.
One of the main reasons why Holden constantly refers to situations and people as depressing is perhaps simply to emphasize that he is telling the story from a mental institution where he has been placed likely as a result of depression.
The other reasons are more difficult to decipher but tend to demonstrate his inability to connect with anyone in a way that satisfies him. Whether it is his friends at school, Sally, and even his sister Phoebe, Holden cannot express to anyone his true feelings or be satisfied with the way that anyone treats him, suggesting that since Allie's death he is incapable of forming an emotional attachment such that he could be satisfied or happy with a relationship with another person.