Hi Nic,
I am sorry you are in such an unpalatable situation at the moment. I feel for both yourself, and your wife and children, as you work through this difficult time for you all. I have enjoyed reading all the posts and seeing the different viewpoints and suggestions. A lot of food for thought here so I hope you don't mind if I add another late thought to it.
Situations that could be irksome can sometimes be handled quite easily simply by viewing things from a slightly different angle. For example a wife may accompany her husband to football matches, not because she likes football, but because she likes her husband. A husband may accompany his wife clothes shopping, not because he likes clothes shopping (uggh), but because he likes his wife.
In this particular case you would not be accompanying your family to please or to displease the elders, or to follow the dictates of some organisation, because they no longer fit into the picture for you. You would be doing it simply because that is what your family likes, (at this time).
It is my experience that a great forte of the male of the species, when their family is involved, is self-sacrifice, followed by another forte of patience. How many years have your wife and children been witnesses? Could you not allow them, at the least, that many months to become unwitnesses?
One of my favourite sayings is 'when the student is ready the teacher appears'. You have the opportunity to be the teacher for your family when they are ready.