Is it likely that by showing our faces at the memorial, we would be back a square one, with the elders chasing after us, asking us if we want a study?
I don;t think that it's that cut and dry. You don't go back to square one. Also, maybe it's time to start practicing setting boundaries. If you go, you can go and specifically tell your mum that she's the reason why you're going, and nothing more. Or you can say nothing, and go back to your own way of doing things.
You don't have to explain yourself to them. You can go to get your mum off your chest and continue with what you are doing.
Besides, I'm not sure that they have the capacity to follow up on every person if they are shrinking in numbers.
It'll be interesting to know what happens. Pleas post what you decided to do and how it pans out.