Why does my husband treat me this way?

he treats me like crap i don't understand he always say its my fault he blames everything on me the littles thing i do he exploeds he this is one he ask me to use my car i said because the night before i told him he cheating on he flip out we got to an argument and i said i was going to throw is drugs away and like always he calls me names says he hates hes going to cheat on and wishes he can kill me that he have thoughts on how and if i cry he puts me dowm more. and its my fault we he's mad me basicalliy im supposed to just deal with him spend lke five hundred on weed a month never takes me out never does anything i ask him to what should i do