It was the alternative meaning of "not-valid" that I found so offensive in this context, and I would have thought that many disabled people would have taken the same view.
The 2012 Paralympics did a lot to reframe the way in which "disabled" people were viewed.
The modern tendency is to focus on "ability" rather than "dis-ability", to look at what someone CAN do, rather than what they CAN'T do. We look for ways around mobility or functional problems so that horizons expand, rather than contract.
I have NEVER thought of my mother as being "disabled", or an "invalid" as a result of the stroke. In the hospital, they referred to her left side as being "disregarded", rather than "paralysed". This phrase caught me by surprise, but makes perfect sense. Not only that, it gives hope for the future.
My understanding of what happens after a stroke is based on the real-life experiences of my friends. So I assumed, right from the very first day, that each "state" that my mother was in - semi-conscious, or confused, or suffering from cramps, or unable to sit up, or unable to stand, was temporary, and that over time she would move on to the next stage. Progress would be partly from natural healing, and partly from effort of will, partly from sheer bloody-minded determination, and partly from rehabilitation.
She is much more "able" now that she was even a couple of months ago.
For example: her handwriting is legible and she writes letters to friends and family every week. She can read a whole novel and manipulate the pages of the book. She can sit up unsupported. She can take my father, step-by-step through cooking delicious meals. Her right hand is extraordinarily dexterous (is that a tautology?). She does her own makeup, styles her hair herself, every day.
The most recent development is that she is able to lift her left knee - it takes a huge effort of will at the moment, but I am sure that it will become easier as she practises. It must be something like learning to play a difficult chord in a new piano piece - to begin with, one has no control over the notes that you are trying to play, but with patient repetition, the movements become more familiar, until eventually one can play the chord without any thought.
I don't think so.
Let's go for
Disregarded left side (which seems to be coming back a bit)
Reduced mobility (which seems to be improving)