At least carry him up and down the stairs when he want to go from one level to the next. Is he in pain when not trying to walk? A friend had a GSD with a similar problem and they got him a cart that supported his hind end. He could go for walks with it attached, but this only works for a dog that is tolerant of such things. I concur with the others that if life is no longer joyous for him the kindest thing is to let him go. The dog I mentioned was in good spirits and didn't seem to suffer.
All, your kind words and thoughts of compassion toward what my Husband and I have often considered are sweet words we needed to hear. He does not appear to be in pain, though I know that this breed often suffers in silence. I tried a 60-day regiment of CBD that didn’t work (I am a big supporter, as I have used it for my migraines with a great deal of success). We do carry him up and down stairs, but he is not a fan; and while he is still in good spirits, we can feel in our hearts this is the beginning of the end: he can’t even stand being in a harness for walks let alone a cart. We will keep this group posted on our decision.
Feed him what he loves, for as long as he loves it. My girl Lady, at the end, would only eat a very few items that she had always enjoyed. She wouldn't touch "dog food". I knew then that the end was close at hand, and I probably should have made a decision earlier, but it is so hard to let them go even when you know that is the best decision. My thoughts are with you in this difficult time.
Find something he does enjoy, might well be nothing like normal dog food, as his liking for peanut butter would suggest ! but give him anything he will eat, just keep the calories going in cos you don't want him going downhill generally.
Good luck - and oodles of sympathy
I probably should have made a decision earlier, but it is so hard to let them go
I know ! I don't remember how many graves there are at the bottom of my garden - a great many. Not a single Basenji in all these years went 'naturally'. I have always had to phone the vet and fetch a spade when the dog had told me, 'this is the time.'
Sometimes I have wondered if I reacted too soon, but I always felt that, for the dog's sake, slightly too soon was better than even a little too late.
Better to say goodbye than to prolong suffering for the faithful friend.
If I am not posting correctly, my apologies: your thoughts/prayers/words of comfort mean so much to me and my family (this is going to be a “first” for my Husband and I, and our 15, 12, and 4-yo). I will keep you all posted; and thank you for all of your comments/suggestions.