Hello freewill,
I'm sorry you're going through a tough dilemma right now. Several years ago, my sister moved out to California to go to college. When she was 20, she asked our parents to help her out with buying a car. We all knew she deserved it: she was doing well in school, had many activities, and she had three jobs. My parents knew that it would be a tight fit if they were to lend her the money, but they did it anyways. While it felt good to do a nice thing, we all ended up regreting it big time. Every now and then we had to end up borrowing money to pay for it. (She would have just sold it, but it depreciated in value so much). So, my advice to you would be to say no (if you can). It's nice to do things for others, but you need to think of yourself first! Good luck!