In Salinger's The Catcher in the Rye, how does Holden show that he has a major depression disorder?

Holden seems like a normal teenager with normal problems. He's jealous of other boys, he thinks about girls, he swears a lot, and the list goes on. Many teenagers think about running away from their problems, too. Holden's problems, however, are deeper than the average American kid's; and, it becomes clearer as the story goes on that he must have anxiety as well as depression. Usually, people without a mental disorder have and apply coping...

Holden seems like a normal teenager with normal problems. He's jealous of other boys, he thinks about girls, he swears a lot, and the list goes on. Many teenagers think about running away from their problems, too. Holden's problems, however, are deeper than the average American kid's; and, it becomes clearer as the story goes on that he must have anxiety as well as depression. Usually, people without a mental disorder have and apply coping skills when they are faced with a difficult situation. For example, one skill might be to find solutions to problems rather than running away. Many people might fantasize about running away, but Holden actually does it! 

"All of a sudden, I decided what I'd really do, I'd get the hell out of Pencey--right that same night and all. . . I just didn't want to hang around any more. It made me too sad and lonesome. . . Besides, I sort of needed a little vacation. My nerves were shot. They really were" (51).

The above quote shows Holden deciding to run away as well a admitting to his sadness and unbalanced nerves. This is a perfect example of depression and anxiety. Holden also says this near the beginning of the book. By the end of the book, though, he has completely gone over the edge and really starts freaking out because he hasn't received the help that he needs.

"Then all of a sudden, something very spooky started happening. Every time I came to the end of a block and stepped off the goddam curb, I had this feeling that I'd never get to the other side of the street. I thought I'd just go down, down, down, and nobody'd ever see me again. Boy did it scare me" (197-198).

Life on the run does not help Holden's anxiety and depression. He starts talking to his dead brother for help and really can't cope properly. It's a good thing that he decides to go home for his sister's sake because that's when he finally gets professional help.