Re: Fiancés mum takes half of his finances
I'm making some assumptions reading between the lines that may be off base, so shut me down if I'm wrong. I'm guessing you and your fiancé are 2nd or 3rd generation immigrants to the the west, and your religion is patriarchal in nature. I'm assuming Muslim, but the specifics don't matter that much.
If your BF is taking care of his mother financially, I'm guessing she is a widow, and that makes BF "head of the family". Is that correct?
I had an employee on my team in a similar circumstance. He was supporting his mother and sister, but his mother would put him in financial difficulties. The last straw for him was when she bought a bunch of new furniture on credit without asking him. His problem was that, as a young man (20s), he still viewed her as an authority figure, and himself as her "child". Nothing odd there, we view our parents as giants into adulthood.
We talked about the fact that he was the head of the family, and in that role, needed to set boundaries on his mother, or decline to support her. It took him a while, but he knew he would be "right" in the eyes of his extended family as long as he treated her with respect as he did it.
Sounds like future MIL has a strong sense of entitlement and no gratitude. He shouldn't be asking her if he can reduce support, she should be grateful for every penny.
You can encourage him to stand up for himself, if you are encouraging instead of shaming. Don't not attack his manhood for having trouble standing up to her. Help him really see himself as the head of the family he is.