My life is a nightmare(plz give really good advice.)?

I have a really bad life. My older brother who has autism, snuck out of my house and almost died. Ever since the day it happened, My life has been 2x as stressful as it already is I've been asked to sleep in front of the front door ON THE FLOOR at like 1 in the morning. How will it work once school starts this august? Ive been feeling extremely depressed and full of rage. I feel like murdering my brother because he effected my whole life's problems. I have been so angry that I stared becoming emo and started to stab myself. I have been so angry that I've been writing very dark poems about my life and other things other prople experience. I have also been having odd mental visions everywhere I go. I nearly screamed out loud at dinner one night.I haven't been sleeping for 2 days partially because of that. MY LIFE IS NOTHING BUT **** AND HORES!!!! no one will give a crap about helping my problems. At school I'm in this language therapy class I don't need at all and it also ruins my popularity in school. Like, ****!! its been like 2 years since ive actually hanged out with my friends. My older sister is like brain dead and wanted another ******* dog and we have enough stress around here. I'm like a servent because of her strict behavior and how she judges my personality and likes. PLZ HELP ME!!!!!!!!!!!!!!