Sorry if this is in the wrong section, wasn't really sure where to ask this.
My sister was diagnosed with MS soon after the birth of her son who is nearly 9. Although it was thought to be mild to begin with DSis has gone downhill fairly rapidly especially in the last couple of years. She did have a degree of independence, being able to 'walk' her son to and from school using a powered wheelchair. This came to an end when she toppled over in the chair on top of her son. Thankfully neither of them were hurt badly, but it became clear that DSis was unable to drive safely enough due to deteriorating eyesight and co-ordination.
Anyway the current situation is that my sister won't do the physio she needs to do in order to stop further deterioration. As she sees it "it's not actually going to make me any better so what's the point?" 
DSis & BIL have a motability car but it has become nearly impossible to get DSis into the passenger seat.
Things came to a head last week when we happened to be visiting. DSis seemed to have almost stopped eating (has to be fed but was refusing) and it was a real struggle to coax her to have her protein drinks. She had to be taken to hospital by ambulance for a 2 week minimum reassessment.
BIL is now extremely concerned for the future. My sister would be 'happy' to stay in front of the telly ignoring everyone (including her son ). We did manage to get her to the park for a while but that was only because my DH (a big bloke) pushed her up a steep hill and wouldn't listen to her complaints. She did have a nice time when there though...almost seemed back to her old self.
BIL now needs to decide whether to go against his DW's wishes and get a new vehicle that she can be pushed into in the chair. DSis wants to sit "like a normal person" in the front passenger seat. I have now come round to the idea that BIL must do what is best for the three of them.
There are loads of other issues but this seems to be the most pressing at the moment. So, how much autonomy should a person with disabilities have? 