No, he doesn't have "boundaries" around your being an introvert. He is, instead, trying to control you by "pushing" you beyond your comfort zone.
You aren't doing a darned thing to him except removing yourself from him when he is drinking. THAT is a boundary. You aren't taking the booze out of his hand, pouring it down the sink. THAT would be controlling--the equivalent of his pushing you when you don't feel sociable. A true boundary, for him, would be to go to social events alone when he wants to go and you don't feel up to it.
He doesn't like your boundary, but that is his problem, not yours. He is trying to twist you up in knots. You are starting to believe the quacking. Just remember--an alcoholic will do anything to take the focus off the REAL issue.