My mother hates me, what should I do?

Im a twenty year old girl and still live at home. Im due to get married in 6 months time and I am so nervous and am desperate for support. However my mother is making things difficult for me as she keeps hitting me, destroying my belongings and spitting at me. She says she hopes I die, rot in hell and never have children (and die in childbirth if I do). My sisters and brothers laugh at her and tell me to ignore her but its really hard as its not nice. I try to just focus on my work ( I work in a nursery) but my self esteem has been tainted even though I keep telling myself Im a good person. What shall I do? Im the eldest child and get treated like garbage even though Im the only one who works in the family and does most of the housework. Yes, I understand she is under stress but why should I get treated like that?