Well, if you're not going to call them out on their shit, who will?

[She's drinking hers down in full, and pouring another one. She knows how to hold her liquor, and doesn't care to be needlessly graceful about it.]

You're the one who stands closest to them. You're in the best position to keep them from doing something that they'll regret, or telling them off when you're too late to stop them.