I need some help..

I’m at the lowest point in my life right now. I’m 17 and I live with my grandparents which is such a toxic household. My mother is an alcoholic and a drug avoider so now my 2 younger siblings are living with us too. No matter what I do in my house I’m always yelled at. Every day. I stay in my room and go to work. I’ve picked up shifts just so I don’t have to be home. I have a dog that helps with my anxiety. I’m told all the time they will get rid of him if I don’t do my best. I’m months behind in school because I have no motivation to do anything. I feel like I’m a burden to my boyfriend. I was at a point a few weeks ago I tried to kill myself. I just don’t know what to do anymore. I’m in therapy but if I say anything to her she tells my grandmother and I’ll get yelled at for hours. I just feel so alone.