How do I survive overbearing MIL & appeasing son?
TLDR: How do I sanely stop my overbearing rich MIL from pressuring my husband to spend money on her?
Setup: Some examples of her overbearing behavior. My mother-in-law started inviting herself and her husband to our house for dinner 1ce every 2 weeks when we got married, in addition to having us at their house 1ce every 2 weeks. I told my husband not to let her but he wants to. After insulting jokes to my cooking a few years back, he makes all the meals. Sometimes she makes backhanded comments about the cleanliness and tidiness of the house. Sometimes she jokes about my husband paying for things for her, like one time it was about him paying for just her and him to go on a trip to some faraway place. When I made a joke about husband having a rate for doing work for them, he told me later that day not to stir the pot. In the past, they made a deal with my husband that if they give him their old good-quality truck, he would give them the $2k proceeds for selling our current truck--all without me in the loop while I was working at a food co-op with 3 young children to help get us out of debt. He swears he'll never make another financial deal with them again. Now, her husband is rapidly aging, and I'm worried that she will pressure husband to spend money on her for lunches and supplies once her husband is dead. They've traveled all over the world and have a $1million net worth. After many conversations about not spending any money on them, on Mother's Day, he paid for her zoo train ticket and her food. Preparing for some future time where I tell him not to spend money on her and telling her "in the act" not to pressure him to dissipate our longterm security for her short-term pleasure is stressing me out. They have support for her husband and he's a very supportive son and I don't have problems with him spending time serving them.
Emotional incest: it sounds like she mainly used him as her emotional support growing up. For the first 10 years of marriage when I had a problem with her, he would excuse her behavior & not ask her to stop/improve because he didnt want to make waves and he "understands her".
Perspectives? Advice? Thank you.