Why me?

I don’t know what’s wrong with me. I have a pretty good life. Other than no friends and the drama I think my life is okay. As I posted before I had a “best friend” overdose on pills because of a fight we got into and the love of my life, at least my teenage love, fucked me over for my “best friend” I have been really depressed, I guess it’s always kind of been there the stuff going on is just what triggered it to start back up again, I was depressed in middle school. I have a 5 year old sister and brother and 6 year old daughter (not biological) and a 15 year old sister. My 15 year old sister just makes things worse on me, she tells me I am a whore, ****, ***** that NOBODY cares about and I should just die, she says things like this in front of the younger ones. My daughter asked me this morning ‘Why I was such a whore?’ , she doesn’t even know what that is. My little brother asked me about a week ago ‘Why I wasn’t dead?’ , my little sister went to school and told her teacher 3 days ago that I was a ‘Whore **** and I needed to die?’ , Her teacher called my mom and my mom sat me down and talked to me, I explained to her that I just want to leave and then she talked to my sister, she told my mom it was me starting it and that she only say it cause I say it first. My mom called me back into the room and told me to not say anything and be the bigger person. I don’t say stuff to my sister because I am scared of her telling people I cut at my new school because I am being transferred to her school. I don’t know why she treats me like she does, but I don’t know how much more I can take. My mom is scared of my sister so she always blames me. I ditch school constantly because I just don’t want to be here. I want to just leave. I have no friend at school so I am bullied a lot, my sister bullies me at home and I can’t take not having a safe haven. I have one but my mom found it so it’s not there anymore. I hate this life. The way I feel. I want to end it but that’s not fair to the younger kids to wonder why I didn’t love them enough to stay. I know they don’t mean what they say because they are just repeating what they hear like kids do but Why does it hurt so much?