Should I be afraid of this monster?

My sister was feeling so down about herself she cut her foot open and sucked out her blood? We sleep in the same room. she got home from the hospital about 2 weeks ago. We have been fighting a lot lately and idk what to do. Im afraid that she is gonna murder me. She already said that she punches/pinches me in my sleep. One time i was snoring super loud so she plugged up my nose and taped my mouth. I almost died. Luckily my mom heard my screams and rushed in. But now my mom is in the hospital because she got hit by a tuba because shes in a maching band. My dad works nights at 7/11 and im afraid that im not gonna make it through. Anyone got any advice for me? I could really use it :/