I have seen a couple of cases where a person just simply won't, for reasons other than possible physical ability, cooperate and make the effort, etc.
OP, these facilities see this EVERY DAY.
As hard as it is, yes, they will forcibly release these patients. They really have no choice. A hospital or rehab center is not a long term care facility.
You should be aware that this is an option that is just not available and will no longer work for you.
If your spouse truly is a person who cannot even get off the couch, who will not or can not use assistive measures, such as a motorized chair, etc, in order to help with day to day needs, then I am thinking that this may be the situation.
We have all heard cases of those who refuse care, which is basically mandating that their loved one be solely responsible for them. Whether their loved one is capable or not, or this would be realistic at all. This does happen. It is an excruciating and sad and painful situation.
This actually almost became the case with my MIL. Her condition was deteriorating daily, and she did not want further and more invasive tests and treatments. All she would do is 'want to go home'. My husband had to sit down with the person at the hospital and tell them, very simply, "My mother lives in a more remote area, by herself, and this would just NOT work, even with a daily nurse visit." And, that he simply could not quit his job and leave his family and go down to her home to be any kind of a care provider.
It came down to DH finding an opening at a long term care facility. My MIL being told, point blank, she was being discharged in 24-48 hours, no question...
My heart goes out to you.
I do hope you are able to find some resolution and respite.