AITA for refusing to share my bonus with my fiancée’s family?

I (30M) work in tech and had a fantastic year at my job. I recently received a significant year-end bonus — $50,000 — and I was thrilled. I’ve been saving for years to buy a house, and this bonus is going directly into my house fund. My fiancée (28F) knows this and was initially very supportive.

Then she dropped a bomb on me. She asked if I could “spare” $25,000 of my bonus to help her parents pay off their mortgage. Apparently, her parents have been struggling financially, and she feels it’s “only fair” since we’re going to be married and they’re going to be my family too.

I said no. I’ve worked extremely hard for this money, and while I feel for her parents, I don’t think it’s my responsibility to bail them out — especially when I’ve never even been asked directly by them. Her response? She called me selfish and accused me of “not caring about her family.” She then brought up how her parents have “sacrificed so much” for her, and it’s the least I could do.

She’s been cold to me ever since. She’s also told her parents about my bonus (without my permission), and now I’m getting guilt-tripped by them. They haven’t outright asked for money, but they’ve made several comments about how “lucky” I am to have extra cash and how “some people don’t get that kind of opportunity.”

When I mentioned that I plan to use the money to help secure our future with a house, my fiancée said, “What future? You’re already showing you don’t care about the people who matter to me.” I don’t think I should have to justify how I use my bonus, but now even my own friends are split on whether I’m being reasonable or stingy.

AITA?