Should I stay out of my parents fighting or is it getting bad to where I should intervene

I (20f) live with my mother(49F) and step father(50M) while going to school.

Some background , they've been together for 16 years , married for 5 of those years. For a majority , they've been happy and had the occasional fights like most married couples do. Most of it was petty stuff that could be resolved quickly and easily.

But for the past two years , my step father has become more cruel and insulting towards my mother basically treating her like a maid rather then his wife. to the point , I have gotten caught in the middle of these fights. I end up screaming at my step father and calling him any name I could think of. A majority of these fights happen after my step dad has been drinking for a few hours or more.

Even when I shut myself in my room , I can hear them and I worry that my mother has just given up on life and everything else.

Any advice I'll gladly take