I want to die at the age of 12 ?

I am a 12 year old girl,We have been living at my grandma for five months because my parents split up.My mum is always chatting on the laptop.I want to move but my mum does not wnat to we are living in one room and my grandma is always blaming me.And then because i mourn abit my 9 year old sister starts shouting at me and gets my grandma to come up with the shouting .She says i am lazy i do nothing and so on. That gets me upset. Every night i get upset and want to die what should i do?????