LPL, I don't see how you could have resolved this any other way. You've warned him, given him second and third chances, and he is still relying on you to look after him.
Tough as it is, it's probably the only way he'll be forced out of his depression and self medicating with alcohol.
Be prepared for him to plead and promise, and try to work on your guilt and good nature. It's important that you hold the line and not mistake promises for action.