Where can I get help to apply for disability?

I'm a woman in my 20s and have been in severe chronic pain and have been trying to figure out the root of the issues for over a year now. Some days it's so bad I am bedridden. I really would like to work as I'm fully financially dependent on my SO rn but again I have difficulty even sitting upright for more than a few minutes some days. I believe that I might be in an abusive relationship in which my SO is pressuring me into doing sexual things I don't want to because SO supports me financially… and then proceeds to guilt me into cutting ties with my closest friends, or telling me SO needs to supervise me when I go out with friends. Today SO told me how much they wanted to slap me out of anger.

I'm so exhausted. They have slap me before but never when we were actively arguing, but more of a "playful" slap for "being a bitch" as a punishment after we would make up after a fight. Except sometimes those slaps hurt and it has gotten to the point where any person's hands close to my face or anyone coming too close makes me instinctively cover my face.

I want to be self sufficient ASAP just for my own safety and independence if needed. I feel so lonely and sad as I'm basically alone at home by myself and he doesn't like me talking to my friends.

I've tried to go through the Texas benefits website by myself but I am overwhelmed by everything and would really appreciate some professional help in guiding me through to apply.