I'm so sorry to hear where you find yourselves.
I'm no expert and can only speak from experience of my own dad's care.
I am surprised they discharged him with no care package in place, that doesn't sound OK. I would find out why the care was refused.
I would contact Marie Curie and they should be able to offer you advice and support. They may also be able to point you in the right direction.
In the meantime if you are able to pay yourselves for some interim help, even just to give you a short break that would be a good idea. We had to this short term as the system just failed to act fast enough.
I would also contact hus GP and council.
Wishing you all the best