My father cheating on my mother

My father has been cheating on my mother from 4-5 years now. He has accepted that as well. And there is not just 1 girl, there are many and most of them are of very young age. He keeps spending most of his salary on them and is not proving enough financial support to my mother (not a working woman) and brother (studying in class 12). My mother has an old mentality and she does not want to go for divorce and she fears separating from him as there would be no financial support for her from any one. Everyone in my family knows about him including his own brother and his children as well, but he is not ready to leave those girls and neither he want to talk about it. His own children has stopped talking to him but seems like he does not care, he never calls them. It was my marriage last month, he took some amount from his office (extracted his PF) but that was not sufficient. We asked him to bring some more money but he denied having any more. My mother and my siblings has been under so much mental stress because of all this but my father does not seems to care. Me and sister does not live with them as we work in another city. There was a time when my mother and brother has made potato and water as vegetable for 2 months as there was no money. We do not have any feelings left for him, we thought that he might realize his mistake after knowing that everybody in the family knows his truth but nothing is changing. Seems like he has become heartless. I would like to know if there is any type of case we can do on my father which can obligate him to provide sufficient financial support to my mother and brother as my mother is not a working woman.