How do I stay pleasant and sane when living with in-laws?

My in-laws moved in with us last month when relocated across the country to raise our son in my hometown.

Previously, my in-laws lived close by in their own apartment, but we had to move them in with us when we moved cross-country. My husband didn't want to send them back to Italy where they have no one to help them besides paid caregivers, and the new town is car-dependent (my in-laws won't drive). So, we bought a huge house to deal with living with them while also working from home.

I have a lot of experience with them part-time living with us at our old vacation home (sold when we moved). In our cabin, they would constantly watch me or need to be in the kitchen at the very moment I would go in, and it drove me crazy. I figured if we bought a big enough house with their own section, they wouldn't constantly be underfoot. NOPE! The exact same thing is happening in our huge house.

I should mention, my father in-law can't/won't do anything for himself b/c he uses a walker, and a week after the move my mother in-law sprained her ankle, severely limiting her mobility beyond hobbling into the kitchen to make a coffee for her husband and then watch me cook, clean, etc. Two weeks after the move my father in-law fell and broke his ribs. Are we having fun yet? I know none of us are, but trust me, they didn't have this extra baggage when they were raising my husband and his brother. They have plenty of money to live on their own back in Italy where they still have a place, they just don't want to b/c then they would only see us when we visit them.

I now hide on the 3rd floor of my beautiful new house that I worked years to be able to buy, just to avoid them, I order dinner in most nights b/c I'm tired of being watched, and my husband stays in our basement where his office is. He's very busy with work, but I think he's also avoiding them.

My marriage couldn't be better. Eye roll. I know the stress of moving is time limited and will fade and my mother in-law will eventually heal and be semi helpful again one day. I say semi b/c she weaponizes incompetence to a level I haven't seen in a woman before. "I couldn't ice my ankle b/c I don't know where the ice is." "I couldn't do dishes/wash clothes b/c I don't know how to work the dishwasher/washer/dryer, etc." This helplessness has been an issue WAY before the ankle injury. She refuses to learn anything new around the house, yet otherwise, is whip smart. She was an impressive businesswoman until she was 70 and now, she can't figure out how to run a dishwasher (mind you, she figured it out in her prior apartments, like 3 various ones in our old town). She's totally bored and annoyed with her husband yet doesn't busy herself with simple tasks to avoid him and help the household, like putting dishes away, b/c to her point "I don't know where things go" (my kitchen cabinets are glass paned... you can see where nearly everything goes.

I go to my parents as often as I can to escape but I'm still living out of boxes. I need to spend more time settling my house instead of running away. I'm currently unemployed, but that will end soon, and work will be an outlet, so there's that, but then new issues arise (them creating distractions and needing me while I'm in meetings).

Mostly I'm just venting to an audience that is likely familiar with this situation, but I'd love to know what others have done to stay nice and sane during times when elderly in-laws or parents move in.

Listing this as relating to the topic of "new to caregiving" b/c I guess that's what I became without really signing up for it, a caregiver.