Drunken father in law taking inferior about me based on my caste

Mine is a love marriage. I am a government employee. My husband works in a private company. My in law family is a brahmin family. I am from backward class. Initially there was no problem. My husband was in dubai. I worked in chennai staying in my husband house. Later i came to know my fil is alcoholic. He uses abusive words against my mil and roam around nude being drunk. I felt very uncomfortable and complained to my husband. He too talked with his father but the condition dint change. Day by day his nuisance got increased. And i later came to knw my mil has hysteric condition. She keeps on argues with the drunken fil and daily there will be ambush and heat arguments having abusive words and sometimes even they beat each other physically. But next morining they will react like nothing happened yesterday night. This repeated almost every day. I got scared and i started to live with my mother for sometimes. Even for that too they created problem. But i dint changed as my mental health was important to me. My husband came to chennai this year and started working here. Fil and mil dint change even in his presence. I noted recently my fil talking bad about my caste which i cloudnt bear. They want me to earn for the family cook for them and clean for them. Without asking them any questions. My husband stays neutral. My uusband also drinks. He beats me sometimes and asks sorry for that. Simply they act like having split personalities. They are different in night than in morning. They easily throw me downwhen they dont need me. Then they will talk sweet when they need any work from me. This happens as a routine and i felt very used up. What should i do. We dont even have kids. These ppl never let us sleep in peace. My husband doesnt agree to live alone. He even has a elder brother who is married. But they dont want the responsibility for taking care for mil and fil. I feel very bad and ineven decided i dont need a kid. I cant raise a kid in this situation. I am so confused. Help me.