I'm scared for my life

My mother is mentally I'll, narcissistic, toxic and aggressive. I woke up yesterday to her blowing up my phone and my boyfriends. Saying it's my fault that her boyfriends dad died because I didn't buy him essential oils to help with his nasuea. He was 99 years old, I have no money and she took my entire stimulus and spent it. Now all day I've been getting messages about shes waiting for a chance to get her hands on me. She beat me from 5 to 15 years old. She ducktaped my hands behind my back to a pole in the basement and left me there overnight. She shoved a pillow in my face trying to suffocate me. She choked me while punching me in the face. She tried to drown me in the bathtub at 7. I'm 20 about to be 21. Shes manipulating everyone in town including the cops into thinking I'm mentally I'll. No amount of texts or video proof has helped me. She took my stimulus and took my ss card and has changed cards countless of times so I cant get it. Now today she is threatening to kill me. None of my family will help. No cops in town will help. Shes gotten away with this for 21 years and nobody will help me. I'm terrified.