My parents used to take my kids to the pantomime every christmas. They still do things with the grandchildren but it does not always involve spending money.
He was invited as was my SIL but as it isn't really either of their thing they declined.
Just repeating the crucial bit in the OPs last post for all those PPs out there who continue to say how the DH has been left out, excluded, not valued, etc. and how they would feel if they had been ‘excluded’ in the same way. Would they really have refused an invitation from their in-laws if their DP/H had wanted to go?
He was invited and declined the invitation!
But he is now saying that, because he will presumably decline his PiL’s next invitation, OP should also decline it’! He is saying that she can only go out with her parents, one of whom has a terminal illness, if he approves of the activity. HUGE RED CONTROL FLAGS!!
In their situation the OPs parents should be making memories (I speak from experience here) and all of the family, in whatever combination, should be joining in with that. No one should be refusing and then sitting in a sulky heap on the sidelines judging the values (monetary, cultural, etc.) of the activity.
Treasure these moments with your parents OP, you don’t get this time over again. Enjoy it now while you can. Make those memories, you’ll be glad you did!