Never get into a financial transaction with a family member

I knew this wouldn't be a good idea, yet we went ahead with it anyway...Two years ago we traded in my parents' jet ski for a newer (but not NEW) jet ski, and now the reality of life is getting in the way.

The timing of the trade-in was horrible...it happened just a month after my dad's surgery. During that surgery they discovered that he had cancer, so he was out of work for about 2 months. My parents didn't need anything more to worry about at that time. They were drained financially and emotionally, and they were also probably dealing with my brother's problems, too.

Additionally, my parents are notoriously irrational. Knew that as long as everything was perfect, that the transaction would be fine (except for the constant hounding about how long we keep the jet ski at our house, preventing people at the lake (read: TIM) from being able to use it).

Now the jet ski is broken. My parents put it in the water at the beginning of the season, and Chris drove it for the first time when we were in Cuba for July 3rd. He said that there was not much power, and that something was wrong. After a little research and some phone calls, he concluded that it is most likely the wear ring, which will cost about $300 to replace. The problem was most likely caused by a rock getting sucked up into the impeller. Now, one could conclude that since Chris didn't drive it at all this season, that it would have been caused by one of the two people who did drive it...my dad or my brother. But now my mom is flipping out at Chris because she thinks he is blaming dad or Tim for breaking it.

My mom's "solution" is that we can get the jet ski fixed, send her the bill so she can pay for the repairs, we can keep the jet ski, but we have to take the trailer back to them so they can get a new jet ski. That makes perfect sense, right? We'll have a jet ski that will make a lovely lawn ornament, and they'll have to spend $5000+ on a jet ski...rather than spending $300 to repair it. Maybe I'm missing something, but I don't see how that's a workable solution.

On the one hand, I believe that if you broke it, you fix it. On the other hand, I believe that my parents don't have the money to pay for expensive repairs. After all, they're spending too much money to pay for all of my brother's mistakes.

This whole situation sucks and I'm stuck right in the middle. I feel like when it comes down to it, I'm disposable. Heck, a couple of years ago I was talking to my parents about something that upset me very much, and rather than listening to what I was saying, they asked about the jet ski. I just want to get rid of it and not have to worry about it. The fun we have on it isn't worth the emotional pain this causes me.