I think regardless of what diagnosis you give the guy you are essentially going to be writing about someone coming to terms with aspects of themselves that have them conflicted or revolted by themselves. Their journey is going to be one of trying to find peace with themselves through a process of integrating this part of themselves they aren't comfortable with back into their functional self. How this can play out or what form this may take is infinite, some might engage in self destructive behaviours and never find peace again eventually becoming homeless and destitute, others might just brush it off and keep on with their lives and others might retreat to a monastery in attempt to find peace with their God. I think the choice you need to make is what does your protagonist want, what are they prepared to do to get it and what will they not let themselves become e.g. do they want to never have to feel the pain of self disgust by spending their days drunk, do they want to repent in whatever form repentance takes in their eyes, do they want to punish themselves in whatever form punishment takes in their eyes, do they want to forgive themselves, etc. There are no universals when it comes to how people deal with things about themselves they do not like or things that bother them.
