What is key to realise about Holden's identity is that, particularly in the area of his sexual identity, he struggles to cope with a massive paradox in his life, which is that he likes sex and is obsessed by it but is also a prude and struggles to remain innocent. This of course mean that any kind of sexual act to Holden is "crumby," which leaves him in significant problems as regards his identity, as he at once tries to place himself in situations where he can have sex and draws back from precisely those kind of situations. This is demonstrated in the way that he frequently sabotages the opportunities that he has to have sex, such as when he is with the prostitute. Note the following quote from Chapter 9:
I mean that's my big trouble. In my mind, I'm probably the biggest sex maniac you ever saw. Sometimes I can think of very crumby stuff I wouldn't mind doing if the opportunity came up. I can even see how it might be quite a lot of fun, in a crumby way, and if you were both sort of drunk and all, to get a girl and squirt water or something all over each other's face. The thing is, though, I don't like the idea. It stinks, if you analyze it.
Holden therefore recognises within himself precisely the kind of sexual desires that he so despises in others around him such as Stradlater. As Holden says just a few lines after this quote about sex, "I keep on making all these rules for myself, and then break them right away." The problem that Holden has with his identity therefore stems largely from his understanding and ideas about sex, and how he sets himself impossible standards to strive to remain innocent and fulfill his own ideas of what he should be like, whilst at the same time finding that his body and his hormones have very different ideas.