My mom keeps getting back with her ex.

I love my mom so much but she makes really stupid decisions and falls for the wrong people, every man she has dated is the exact same but looks different. Criminal record. Anger issues. Abusive to animals. Yells at me and my brother for small things.and so much more it's so annoying he's so mean to me and my brother and yesterday he was threatening to hit my mom and she said she was done with him and then she got back with him last night and I cried all night and I tried to tell her how it made me feel but she just doesn't understand. She's such a good mom, she's so understanding and kind but she physically cannot get into a good relationship and it makes me so upset to see my mom date the same person over and over again and the same thing end up happening. There's a cycle. Date, argue breakup, make up, date, argue, break up, make up and repeat until she finally has enough and then a month later she will be dating another guy that's the exact same and me and my brother will tell her she doesn't need a relationship and a man but she physically cannot be alone. I love my mom so much and she doesn't deserve to have that kind of relationship but it's also affecting me bc yesterday I had a panic attack thinking he was actually going to hurt her and I got sent home bc of it. And she doesn't see it how it affects me and my mental health. All of her boyfriends seem to hate me more than my brother. It's so annoying.