i hate my life. everything i do and everything others do, i just hate

i hate my life. everything i do and everything others do, i just hate. nothing makes me happy anymore, it hasnt since i was 13 0r 14.no one understands or cares. if talked to my parents and my doctors and they say im fine. they dont do anything.. im in so much pain and i just want it to stop. theres nothin else i can do. in the past yr. ive started cutting myself with razorblades, picking at myslef with safety pins, biting my fingers till they bleed. its the only thing that makes the pain go away....and its not working anymore and i just want it to stop. i really just want to die, i dont see any other way. i hate myself so much for being this way, but i cant help it and no one wants to help me and i dont think anyone would care if i died anyway. im sick of being in pain, and lately ive been hearing voices in my head, telling me to just end it, and no one believes me. i feel like im completely insane and no one cares at all. i just want to scream and fall and cry all the time, but i cant, im constantly holding in my emotions, and everyone always thinks im the happiest person in the world, but what they dont know is that i feel dead inside all the time and i just want to be dead. i cant remember a time when i was happy...is there any advice?