money was a feature in my family too
things would be okay, we'ld be offered some money for something, and then the claws would come out but we wouldn't feel able to speak up because we were indebted for the thing that being paid for.
I feel that money was used as a way to make us a captive audience to however badly she wanted to behave.
We stopped accepting it. And it made her behaviour worse actually, she seemed to be very displeased that she didn't have something we needed to hold over us and dangle on front of us. But, even though she was acting far worse to us when we decided not to accept any money at all from her, it made it easier to cope with because we didn't feel "ungrateful" if we spoke up for ourselves.
There was a power thing when she was giving us money, we were a bit powerless, and without taking money we were able to be more on a level with her.
I think by not taking any money you can say: "I don't need anything from you, but I would like a mutually respectful relatinship with you"
It might not work, but it sure made us feel better to take away the money dynamic out of the equation.