This has lasted for over a year but much more noticeable in the last few months. Looking back, it could have started even longer than a year ago,
I have done almost everything you mentioned, ie tell him I don't want to live like this and that I need to know why he is behaving like he does. He doesn't have any close friends as far as I know and he hasn't spoken to any of his family, in fact, he has become distant to them too. I am planning to find a counselor but don't know how to go about it. Can you suggest? He is unlikely to go.
It sounds like you have tried everything you can to make this work. I'm sorry you have to go through this.
Here are some resources to help you find a therapist:
Here is a link to help you find a good therapist: