Living with Chronic Pain and Family Frustration

I am feeling really frustrated with my mother and family. I have POTS and Ehlers-Danlos syndrome. My quality of life isn't the greatest. I live with my fiancé and I'm trying to get on disability because I cannot currently support myself in any other way. I take 3 to 4 tylenol when I wake up and before I go to bed and even then I am still in pain. Getting up in the morning is a task within itself. My mother has chastised me for wanting to be on disability because of my pain and the fragility of my body. I cannot work a normal job and my fiancé has been trying to support me in the meantime. It hurts when I try to talk to her about my pain and she gives me examples of family members or other people that have worked despite their pain. I have always said "good for them, but I am not them and I can't do it". I'm not sure how to make her see I need disability and it's become frustrating. She blames my fiancé and thinks I lost my drive to work because of him. This is very far from true. I simply cant work, my spinal fusion has also left me in chronic back pain. She likes to pretend my pain isn't as serious as I tell her but she used to advocate for my pain when I was in school. I'm left feeling frustrated and upset. I would have chosen disability even if my fiancé wasn't the one to introduce it to me.