I read this first when I was a sixteen year old adolescent who still thought he was a girl. I identified with the angst, the delirious anger, and a general preference to feel sorry for oneself instead of opting for vulnerability and opening up. 
Because I, too, thought that I was being rebuffed and ignored and I, too, was being rebuffed and ignored because I couldn't fully get out the thing that wanted to come out without giving myself away. 
Now that I've read it again as a twenty three year old trans guy I don't have much in common with Holden except for our mutual concern for the ducks' wellbeing in winter.