Revenge Tour, I sure feel for you, having been in a similar situation not too long ago.

Your situation sounds very similar to mine in regard to house size and use. We have three bedrooms, with one being the master, one for DD, and one is a birdroom/workroom/storage room/reading room. Other people may look at that third bedroom as a "spare room" but it's really not. There is just no extra room to realistically accommodate another person, particularly an adult who is going to have their own strong preferences from a lifetime.

My situation was a little like Tisha Buv's with my father in early dementia and needing more supervision. But he and I were not THAT close, he was the worst snorer who would do nothing about it, and of course he was a little entitled about how things should be. Let's just sum it up to say that it was unworkable.

And I had the brother who wanted to dictate how everybody was going to live and what everybody was going to do, and how everybody else was going to modify their life to accommodate dad. And it's not a point of not wanting Dad or not wanting to help dad, it's a point of your life goes on even through our parents getting older. It's great if you can help them, but it can't be at a high expense to yourself or you'll be no good to anyone.

Maybe I'm projecting here, but my gut feeling is that your sister-in-law's being like my brother is a big part of the problem. There's not really this mutuality to figure out how to make this work, she's already figured it out and her head, and that's making it worse for you. I totally get it, because I was there at one time.

Can you think of anything that would work? A way that your sister-in-law could have less burden, but without disrupting your household in an unacceptable way. Does the sister-in-law live close? What's mother-in-law's living situation when she's with the sister? Does she have her own room there? I have a few relatives that all have a couple of spare rooms, so they really don't get what it's like to not have any extra space that you're not using for your family. Is it possible that the sister-in-law is close enough that mother-in-law could spend extended days with you, but sleep at the sister-in-law's house? Can you think of some other scenario that might work better for your mother-in-law? Would she be capable of living in a senior community and perhaps spending days at your home here and there?

This is one of the toughest things that I've had to deal with, because if you say no to preserve your own life, there can be this undertone that you don't love Mom, that you're rejecting her, when that's hardly the case at all.

And in the end, after dad had passed away, I didn't have this point when I looked back and wished I'd done it differently, because it really was an unworkable situation. We didn't have the room or the lifestyle to accommodate an older person, and he was not a person who was willing to give much in return to slip into our lives. Then add the overbearing demanding brother on top of that and it was never going to work. Those are facts not justifications.

Find a solution that works for you and your family,and stick to it, just remember, polite boundaries, but boundaries nonetheless.