Mental harassment by mother, her lover and my brother

I am 25 year old, Female. My father passed away in Nov.2023 to which I have bore all the financial burden of.I have been on my own ever since I turned 16, completed my bachelors and masters strictly on scholarships my parents have not given me any financial support ever since instead I have been mentally and emotionally sometimes physically too harassed by them.I do not want any ties with my so called mother and my brother but they just won’t let me live in peace and keep calling me and the people around me and abuse them for no good reason.I have always duly completed my duties as an adult daughter but the burden just won’t lessen and they keep asking me for more and more financial help when I myself am in a drift. I want to get married but they have not once but twice called up even the guy I wanted to get married to and talked rubbish about me to him. My mom has been having an affair with a family friend who has also been verbally abusing me for a while now. What legal action can I take to stop them from making my life hell.