What are some examples of Holden Caulfield's negative self talk?

Throughout the novel, Holden is grappling with grief over the death of his brother, Allie. That grief is often experienced as guilt for his powerlessness to help him while he was sick with leukemia or to stop him from dying. Although Holden sometimes expresses his desire to help in positive ways, such as his child catcher fantasy, more often he internalizes his negative feelings and denigrates himself.
Some manifestations of Holden’s negativity are played out in his poor relationships with his roommates. Although he knows that Stradlater is a bully, he feels powerless to resist overtly and instead pretends to help him cheat by writing an unacceptable essay. After their disagreement erupts into violence, Holden becomes so despondent that he expresses suicidal thoughts: "I felt so lonesome, all of a sudden, I wished I was dead."
Although Holden tends to speak in hyperbole, his frequent references to his mental health have some basis in reality. He frequently refers to himself as “crazy” or sometimes as a “madman.” An example is his conversation with Sally, whom he tries to convince to run away with him. She (rightly) dismisses his idea as “fantastic,” and they get into an argument. After Holden leaves, even though he knows he behaved badly, he feels conflicted, both laughing and depressed. “I don’t even know why I started all that stuff with her . . . That’s the terrible part. I swear to God I’m a madman.”