Thanks, Theresa (Comment, below). She was a heck of a cat. I'm hoping it helps others, too, when their cats stop eating and drinking. They won't try to force feed or hydrate or otherwise interfere when an animal so wise is working with its own personal death project.
They can just make sure the cat is comfortable and quiet and gets to sleep where it wants, and maybe hold it a little if that's good.
(And a good dvd to watch if holding is in order — "Dead like me." Helps us deal).
I think I may know why cats do this. If you starve and dehydrate at the end, there will be nothing but skin and bones left. Nothing really edible to rot and bring in the predators that may go for your relatives or half-grown kittens (hey, it's a theory).
Wise animals, cats. Right down to their DNA.