New puppy, or not?

I've been having a lot of trouble coping with my spinal stenosis, and it's getting me down.
Stuff that I took for granted is becoming more difficult to cope with.
And because of this, I have been questioning the sense in getting another dog.
When I am having a good day, I feel confident that I would be up to looking after another dog, plus I think Shadow gets lonely at times.
But yesterday, I seriously doubted myself.
It would help if I knew more about my condition.  To me it feels like it's getting harder to cope. Is it degenerative? Where do I find out? Are there any support groups.
I wasn't feeling that I can't go on any more, just that I need help learning to cope, which is very hard when you essentially live alone.
Oh! By the way! I was thinking that maybe a Bengal cat might be a good compromise.