I've raised £5400 to Help my disabled mother.

She currently has been refused at tribunal by the dwp due to the fact that she can 'sit for long periods' despite the fact that she has fibromyalgia, plantar fasciitis and arthritis in her back. If you're not aware fibromyalgia, is a condition that effects the body but also has a neurological effect. They were not only rude and unhelpful but they've left her in a position where she cannot pay for her utility bills and is 'robbing Peter to pay Paul.' So to speak.
Upon doing my own research, I've found that even if she did apply for work, many are unlikely to hire her due to the fact that she has a long term debilitating health condition, let's not even get into the fact that she is 63 years old.
The neurological effects of fibromyalgia mean that even if she were able to secure employment, she could not guarantee she could get there on days where the pain is too bad, or when she is she too fatigued. On the days that she could attend, she would be unlikely to retain any useful information because of 'fibro fog'. They completely ghosted over the fact that she suffers with ptsd/depression due to domestic violence.
Unfortunately, all of these factors have left an old lady very terrified and in more debt than she knows what to do with.
Why is it so difficult for people with fluctuating and long term health conditions to get the help they need?
I will be starting this in the hopes I can help my mother out of some of her debt, I'm giving her everything I can but as a single mother, it's not enough.
Please help.