I think anger is a defense of fear. I don't think addicts are so much angry as they are afraid. What are they afraid of? everything IMO. They are afraid to live and afraid of dying, they don't know how to live, they are fakes and, they are afraid someone might find out how afraid and what a fake they really are. So they go into their own little world where they can hide and not have to face their fear where they can fantasize about how great and powerful they feel.
They have to be very dishonest with themselves and others in order to keep up the charade to be that seems awfully fear producing...