I'm mad at my disabled mom
Why do you feel that way about her?
She can't live on her own and needs constant help.
You shouldn't be upset with her so much.  She doesn't have any control over her disability and therefore it's wrong to be angry at her over something she didn't choose to be.  Try and be a bit more understanding!
I will say it's her fault for not doing anything and that she can do better.
How can you blamer her if she had a physical disability? She tries her best every day and it is unfair to assume things because you feel frustrated with the situation. Have some respect.