Re: Fed up with Sensei
He needs to be confronted about his behavior for his own health and that of the dojo. Alcoholics are classically surrounded by 'facilitators' who support the alcoholism by pretending that nothing is wrong, calling into work to say that the alcoholic is sick when they actually have a hangover, etc. It keeps the alcoholic from having to face the consequences of his actions.
It may end your relationship if you decide to confront him on this, but if you truly care about him it would be the honorable thing to do.