Why does nobody like me ?

I'm 12 and I'm in middle school. I feel that nobody like me,not even my family. My mom yells at me all the time and blames me for everything. And mi sister nd brother are always telling me nobody like you!! So I get really sad and depressed and since all of that has piled up inside of me I always run to the bathroom and stay there for a while and cry.I feel like I don't want to live anymore.everybody hates me and it hurts. I just don't know what to do my oldest sister is the only one who really loves me nd I love her I just need help. I want all my problems to; POOF! Go away . Somebody help please!