My RAH while relapsing would not get angry at all when I brought the subject up. He would very quickly state that 10 years sober was proof that he was not an alcoholic. He would sometimes mention hosts of documentation that he had found on the internet supporting his theory without being able to produce it (I'll get it for you tomorrow which eventually turned into "If I have to produce it for you then you don't trust me")
Of course he also denied he was drinking multiple times even once while holding a vodka in his hand.
Good luck.