I read you other post along with this one, and just wanted to give you my opinion.
From my own experience, I can say that being able to open up and talk about my abuse is a really difficult thing to do. I know talking is supposed to help, but for me on the rare times I have shared my experience, it brings up a lot of bad memories, and the feelings attached with it. I've only just realised that by opening up, I have actually been pushing those same people away, possibly as some form of defense mechanism to keep myself isolated.
The only thing I can suggest is to let him know you have been researching, and trying to understand what he is experiencing. However don't push him to open up, as it may drive him further away. Let him know you are trying to understand, and you will be there for him when he is ready.
I've only found this site recently myself, and I think that by letting him know about this site, he may come here and find the same thing I have - that he is not alone in how he feels, and there are people he can talk to that understand what he has experiened.
It may very well be he opens up here before he talks to you about things. If that is the case, don't take it in a nagative way. Just be greatful he is taking steps to open up and improve his life.