i cant live in my house anymore

its a long story..
my sisters bf? xbf is the worst man you could ever think of, steals,cheats,LIES,HITS,yells, anything you can think of, and im sick of living liek this, having to put up with all her crap, my parents cant take it but htey dont do enough i mean im only 15 but im trying, and i have my own life to but i cant beaucse im surrounced my everyone elses problems, and this is just enough, hes stlaking me now!and i just cant take it, and the stupid police wont do anyuthing, arrets or anythign even if he does have liek 10 cases on him, and i just dont know what to do anymore, and my aprnets dont want my ssiter to move out cuase she "cant handle it" so im stuck here, and i dont wanna be IM DEF. done , done for good, im either just gonna die, or i need a place to go. becuase i cannot take this anymore....and i hav eot deal with school and im starting to fail calsses and im TRYING and TRYING but its no good, and love just hurts, and my friends, ,haHAHA they talk about me and i can trust anyone....
theres so much stuff, idk if i can take it.