Is it the highest stage? I help my mom?

I've a brother who's a doctor already, and he's doing his specialisation in onco-surgery. He's in the second year of his residency (a part of the specialisation course), and he's had to face many severe problems there. Obviously my mom would get upset due to that and naturally she'll cry. But idk, since almost a year, she's getting so hype over PETTY issues (literally petty issues), and she keeps Harming herself, she keeps beating my grandmas (my naani and daadi), and trust me that really kills me. I cant tolerate anyone beating my naani and daadi. I feel suicidal. My mom has a problem with everything almost every day. She keeps comparing her and my relationship with other mother-daughter relationships. Idk if I'm the bad daughter here, idk. But I can see a drastic change in me too-I've stopped talking much due to all this chaos. I can't concentrate on my studies. It is my boards this year, I'm in 12th grade. Please help, how can I help my mom?