I ride fixed in hilly terrain often over long distances. My better half is one of the finest exponents of riding a bike you will ever see and we do hard training rides together, but, and it is a big but, compared to your rides they are minuscule . I always read your ride reports and greatly admire what you manage, I am not at all sure I could do that.
Friends are the key thing here, there must be lots of barmy CC'ers in your neck of the woods who could pop by and chat or ride a bit with you when you are able, I know I would, and would consider it a privilege to do so. If I/we ever find ourselves down your way I will drop you a pm and arrange to meet up.
I hope medical science is making progress in your area of need, new advances are being made at a seemingly exponential rate in many different fields so don't give up hope, never give up hope.
Now you lot, start making contact with cosmic and see what you can do.