Contact Social Security there is a benefit for people who are in your mothers situation, maybe it is called SSI soc sec income, it is for people that have no other means of support, and they make fast decisions, I would call them ASAP and also ask them about Medicare and Medicade and of course she should apply for SSDI which is Social Security Disability Insurance
and what about Food Stamps which is hard to accept after you have been a contributing member of society but it is at least something, and HEAP for help with heating, I think that takes a bit of time but at least by applying now and not waiting you are making an effort and the utility company would like that. She should have been offered COBRA from her job, which is a continuation of her coverage, but that can get expensive
I was fired from my job also because of MS, I live in NY and it is a hire and fire at will state, I had used my Family Medical Leave before I was fired, did your mom go out on disability on the FMLA? But I like what 6foot3 said about the disability act, I would for sure look into that. But whatever you do, do it like yesterday, because it takes time for approval expecially SSDI
and finally contact your local chapter of the MS Society for help and if your mom is on medications, I see lots of drug companies that help people that are in her situation.
If I were you, I would ask for all that I could, go online and start searching for any assistance and not be too shy about it, because it is the "squeaky wheel that gets the grease"