How do I get my parents divorced?

My parents and I live in India, where divorce is still seen as taboo to a great extent. My parents have been married for 25 years. But it was never a marriage of love. It was an arranged marriage. My father has always seen my mother as a responsibility. My mother perhaps loves my dad but that probably comes from a kind of stockholm syndrome and her sense that it is the wife's duty to love her husband. My mother grew up in a small town and my dad never allowed her to work. She had me within the first year of marriage and suffered from post-partum depression. My dad got her good food and everything but was never there for her emotionally or for most of child care. He never cared to help me with my studies or anything. His attitude has always been that if I provide for my family, that's enough. My dad was still fine I guess, had fairly liberal views and believed to some extend in equality of women. But with the rise of the BJP, hindutva and all the things wrong with this country in the past ten years or so, he has changed drastically. He has become very islamophobic and misogynistic. He has become a very vile hate-mongering person and I can't recognise him anymore. He is always angry and tries to control my mother. My mum should've honestly divorced my dad in the first year when he onlt aggravated her post-partum depression but she was brought up with the thinking that once you marry, you marry for life. I know she deserves so much better, but she is now stuck with this asshole of a husband. I am genuinely scared what this man can become in the future. I am now financially independent and I guess I can move out when it comes to it. But my sati-savitri mother will never leave his side. How do I get them divorced?