I mentioned the terrible behavior at the dinner table.
I actually did speak to W about this the very next night. In a strong and direct tone I said that we were both out of line to speak like that in front of kids; and asked that we not do that again. W agreed.
I did not state a boundary but could it be, "I will not talk of MR issues in front of kids. If you (W) talk of MR issues in sarcastic tone I will remove myself and kids from your presence until you calm down." As long as I can remember what I said I will do.. this should be fairly easy for me to follow through with and don't see why she would challenge this one.