I'm sorry for what your mother and the rest of your family went through. I have no doubt that the company acted unfairly. Encouraging an attitude of fatalism and "they'll screw you no matter what!" is only going to exacerbate the problem. Companies will only continue to get away with things like that if everyone just accepts them as a fact of life.
I actually think it should be really easy for a company to fire someone, for whatever reason they want to.
And I think we should have social services that make you not fear for your life to be unemployed. Free education. Free health care. Basic Income on top of that.
Sure, I'm all for that. But as long as we have this system where we want corporations to be responsible for citizens' welfare instead of the government, we should make them step up to the plate and actually do it.
Encouraging an attitude that corporations can be responsible for citizens' welfare is only going to exacerbate the problem. Governments will only continue to get away with ignoring citizens' welfare if everyone just accepts it as a fact of life.
And yes, my mother, while going through cancer treatment, was pretty much powerless, regardless of how she wanted to act.