How to leave a toxic relationship?

I am in a toxic relationship and want to leave but I dont know how. We have a 3 year old together. I have no friends outside of his friends anymore and no family. Ive reached out to DV assistance places but I get turned down because other people in more serious situations qualify more. I have a job but every cent goes to rent or other bills and I have no ability to save to get out on my own, I wouldnt even be able to keep my job if I were to leave because I use his car and we dont have child care so we alternate shifts. How do people leave situations like this?