<human>: Summarize the given text in a few sentences.

Throwaway with some details changed just incase. Basically I love my SO and am going to marry her.I had a pretty lower class upbringing whereas she was fairly middle class. Her brother made poor financial decisions and basically ended up bankrupting her family.

Despite this, me and her are dealing with our own personal finance (wedding planning, future school debt, etc.). My fiance supports herself and I support myself until we are done with our personal goals. Anyways her brother recently came into a situation where he needed money (75,000-ish$) and had exhausted all his finance channels. 

Her family asked her for it to help her brother (and she would help them in a heartbeat...) but she didn't have that sum of money available. They and the brother then asked her to ask me for it. Now here's the thing, l've never received a hand out and never given one. I'm absolutely against the idea of even her giving money to anyone but she's not my wife and its not my decision, yet (she thinks it won't be a problem once she's married and has her own family...). 

Regardless I turned her family's request (thru her) down, but am left wondering how I'm going to establish a proper relationship with her family once we are married and they ask me directly for money. I earn a decent amount of money, and with my fiancé we make six figures. I live really frugal at the moment but as soon as I hit 30 I will make my dream car purchase that may expose my "money". 

Basically I just want some advice on how to set a foundation with my future in laws that they won't see a penny from me or her in the future. I do believe in helping family and supporting them, and they're wonderful people, but Im not going to be a sucker like my fiance has been the last 26 years...these people are reckless with $$.

 My fiance is on the same page as me but I feel bad when I show her the bigger picture because she wants her family to be better at the same time. How can I hold my ground and make my fiance not feel guilty about it?
<bot>: have a feeling future in-laws are going to ask me for money. Going to turn them down but I see disaster happening when I buy an expensive car worth more than what they asked.