Your sitch sounds exactly like mine did 20 years ago...except the divorce thing. I'm a guy and spent 9 months in chemo and radiotherapy. My W wasn't there for me. I was disappointed that she was not strong enough to support me. I'd be laying in bed, vomitting my guts out into a bucket and she would walk up, close the door and go back to what she was doing. She couldn't deal with it at all. It wasn't that she was insensitive or didn't care, she just couldn't deal with it. It was only later that I'd hear that she would go to our best man and wife's place and cry her heart out for hours.
I resented her weakness and lack of support. As soon as my treatment was done and the doctors told me all I had left was scar tissue where the tumors had been, I rejoined my rock band and we 'temporarily' move to another state. For 4 months, I had left my W behind, didn't even stop to think of her because I was having so much fun. I even resumed my career and as a happy 24 year old, I was living with my birth family and life was looking good. W pursued me and my mother urged me to bring her across. In hindsight, that was a HUGE mistake and my mother has regretted that advice ever since.
The last 20 years have been tough. Because of the chemo, I lost my ability to father children. Took the option of donor insemination. Another emotional crisis I had to deal with. It's been a comedy of errors ever since. For before I got married, I was a happy and healthy 22 year old with the whole world at my feet. For the last 22 years, all I have had is misery with this woman and I have had enough of it.
Perhaps I am painting a picture of a probable future for you. I can completely understand your xH and how he feels. While he is in remission, he still has 4 or 5 years of being this way before he is clear to look forward to a becoming an old man one day. Having survived cancer myself, it places a huge and daily emotional strain on you daily if not hourly.
Your xH is at a very vulnerable point, the best way you can help him is to give him the gift of time and space to see his own way forward. Just remember, this is not about you, it's about him, his disappointment with you and whether he will make it through or not.
In sickness and in health, for richer or poorer.....it goes something like that. When it came to sicker and poorer, my W is a complete failure. She never took the opportunity to learn from what she had done. I sincerely hope that you do.
Suit
"It's better to have no spouse than have a bad spouse"