There's a very fine line between love and hate sometimes -- the more you love someone the easier it is to feel hate when they let you down or hurt you. There's a whole lot of emotion churning inside both your boyfriend and his mom and if they don't find an outside "outlet" - besides booze - it's going to continue to churn until something gives.

It's perfectly fine that he is angry - but he needs to learn how to deal with this anger. This is a lifelong illness that she has to deal with and she needs all the support she can get - but until your boyfriend gets past the anger - he won't be much help to her, himself or anyone else.

Talking to you is upsetting you - because you're lucky enough to have a wonderful relationship with your mom and it's hard for you to relate to his anger at his mom - and that's why I suggest again that he gets some outside help. You don't want this to come between you two and no one wants this to upset you enough to make you ill.

By the way, I think that you're a pretty special person to be willing to go through this with him. ;-)