I'm sure he does want some form of help. I know myself I have often given the "I don't want to talk about it" and "I don't need help" line's, when in fact all I want and need to do is sit down and talk through it.
When I first told someone, it was difficult and I instantly panicked and thought I had done the wrong thing. It was like I had been exposed for what I really was and I didn't like that after keeping it a secret for a long time.
If your boyfriend is having a hard time discussing it in person, have you thought about writing him a letter so he can just sit and read it. Then there wont be any confrontation about how he 'doesn't need to discuss it' and you can get your point across how you would like to help him.
Deep down, I am sure he appreciates your concerns and it may just be that it's such a difficult thing for him to deal with, he doesn't know how to react now that he has finally spoken up about it.
Please don't give up on him. Tell him that you want to help him. Explore the options for therapy (either for just him or for both of you together). Maybe introduce him to this community? Finding this place was a big step for me, i'm sure he might appreciate it since it would be a place for him to vent to people who understand him.