My (27F) parents (both 65M/F) can’t stand each other and “family” time has been absolutely awful, how do I tolerate this???

My parents are both 65. My brother (23M) and I (27F) are both moved out and living on our own. We have always known our parents don’t have a good relationship was not a good one. My dad is an angry and my mom is a pushover (for lack of a better word) who just put up with it. Now that we are gone, there is less tolerance with her to deal with my dad. Both of them CONSTANTLY bicker, talk bad about the other to me, and just cannot co-exist with each other. I’m getting to a point where I just can’t fucking stand being around both of them at the same time. I have tried talking with them about what I am noticing and how it impacts me, and their own well-being. But it doesn’t seem like either of them are willing to change something to better their situation. I have came to a point where if this is how they are choosing to live then there’s nothing I can do about it. It’s just hard go watch them be miserable together as they age.

Also- the reason they won’t divorce is because my mom was the only one who worked my whole life providing for my brother and I, and also my dad. My dad got a huge inheritance that my mom wants to reap the benefits of instead of divorcing and giving half of her earnings and come tuning to struggle financially forever. Idk. Just the reasoning they tell me so I just don’t know how to tolerate this at all