Stuck with an abusive man who's threatening us

Okay… I don’t really know where to begin, so I’ll try to keep it short. After going through a very difficult marriage, my mom divorced my dad and later got into a relationship with another man, hoping for a better future. We lived with him for a couple of years, but he turned out to be a narcissist and an alcoholic. He constantly controls her, badmouths her, and mentally abuses her. My mom is very naive and feels helpless, so she hasn’t been able to take any strong action against him.

Last year, I made the tough decision to leave that place with my mom and settle in Madurai. It was extremely hard. Even now, he keeps coming and going because my mom is unable to cut ties with him. He threatens and blackmails her, saying things like he’ll k.ll her when she goes to work, that she ruined his life, that he doesn’t care if her kids are left alone after killing her, and that he’s fine even if he has to go to jail. Because of fear, my mom always asks me not to take any action.

But this time, things have gotten worse. He keeps threatening her just because she doesn’t stay in touch with him. He abuses me and my family verbally, and whenever he comes, we’re unable to make him leave the house. We live in a rented place, have no relatives or close contacts nearby it’s just me and my mom.

I’m scared that if I go to the police and things escalate later, our situation might become even worse. I’m currently a student (23M from Tamil Nadu), and my mom is working. We don’t want to keep going to the police station or deal with constant trouble that disrupts our lives. This situation is constantly running in my head, and honestly, I don’t know what to do anymore. I don’t remember the last time I felt peaceful living my life. I really want to put an end to this situation.

Please share your suggestions.