You took the high road.
Now, there can be a price to pay for taking that road. Sometimes it's worth it though don't you think?
You could have screamed and yelled, you could have punished him, could have withheld affection and maybe thrown in some side ways glances as he poured another drink.
To what end? Perhaps you think you might have felt better venting that frustration on him? Really, probably not. It would have just changed the dynamic in to something even more destructive (not just for him, for you).
Could your boundaries have been stronger? Maybe, that's something you can work on now if you think that is the case.
So this:
he would have 'chosen' to drink no matter what?!
Do you honestly believe this, I mean really believe it, no doubts? It is true but if you don't truly believe it, it can be a struggle.
Still chatting to him while carrying around these questions and resentments might not be all that good for you. Perhaps a period of no contact would be better for you?