Ex-husband harassing me

I was legally separated from my husband in March 2019 on the ground of alcoholism, domestic violence, and increasing demand for money. Now, I am a single mother of a 15yr old boy. After divorce, we suffered a change in the behavior of my parents and sisters towards me and my son. In fact, my own father started to physically molest me. I tried to seek help from my mother and sisters which was a failure. By profession, I am a school teacher and that's the only source of livelihood for both of us whereas my ex-husband was unemployed. Last year March I and my son decided to give a second chance to my ex-husband as it had become difficult for us to live with my father. We moved to his place in Indore without letting my parents and tried to mend the broken strings of relation for six months with him but he was back again to his old mode of behavior. This time it was too severe. He has beaten me to bleed and he threatened us of informing my parents that we were staying with him, which we didn't want to happen. In September I left his place with my son without informing him. He kept searching and in the meantime, he had taken out my call records and started calling and troubling my friends and relatives whomever I have spoken to in the last six months. We don't want to live with him anymore because it's life-threatening to me. I want to know that if he is ever able to trace me what I can do to protect myself and my son from him.