If the mood in the room changes, you’re allowed to change rooms.

Rooms have a temperature, and you can feel it shift before anybody says a word. Staying put while it turns is a habit rather than a duty; no prize is handed out for sitting through something that has started going wrong. Leaving quietly is often the entire solution. Your reason does not have to hold up in front of a judge.

Give yourself one exit line you can use without rehearsing, something as plain as needing to head off. Use it once this week when a place sours, and notice that the evening survives it.