Good catch, Telly! I didn't notice, at first, that the op and dd attended an event of mil's without dh. It was very kind and caring of you, anonymous, to want to be supportive of mil. The fact that dh chose not to be, plus his difficulty in speaking up to his parents are clues, imo, to the fact that something is very wrong there. Maybe you didn't see that before, but hopefully, now you do. Has dh ever opened up to you about any concerns about his foo (family of origin)? Regardless, in the future, please follow his lead. If he chooses not to go to an event, don't go there with dd either. That will be part of lowering contact, as well.
Advice please - caught in the middle
Boris vs. Jeremy - thoughts?
What weren't you allowed to do as a child? - making a fuss