Have you tried psych drugs for your cat? Buspirone helped my neurotic cat be a LOT calmer. Plus, if your household being turned upside down is a short-term thing, you can use diazepam (Valium) to calm him down. Unfortunately you can’t keep cats on diazepam long-term because it can cause liver damage ... but OTOH, if your alternative is to put him to sleep anyway, you might feel comfortable risking it. (Usually vets want you to get them off diazepam within 5 days.) If I were in your shoes, I would definitely try psych drugs. You will need to talk to your vet to get them, but they are not expensive. (And if your vet has seen the cat relatively recently, say within the last year, they should be okay with prescribing the drugs over the phone so you don’t have to pay for a vet visit.) You should be able to get generic drugs cheaply at Costco or someplace.
To go to the ethics of the situation ... I too hate to put an animal down who is simply a problem, rather than actually being ill. It is a tragedy when that happens. I really urge you to talk to your vet and go for the psych drugs. Iffen it was me, I would start the cat on buspirone immediately since it takes a while to kick in, and put him on diazepam immediately as well, to keep him calmer while the buspirone is starting to work. Then by the time you need to stop the diazepam, the buspirone might have started to help him. Your vet may have ideas on better drugs as well. Good luck!!!!!
I have just had some upsets with my 12 year old kitty, Ebonie. She too licked her tummy bald and I had her into the vet umpteen times to try to sort out what is going on...she also had troubles with her anal glands...soiling outside the litter box and scooting....finally an outstanding surgeon removed the glands and no more licking which drove me nuts and the potty problems are solved too. One hitch, the meds given post surgery sent her into seizures..those seem to have resolved now too but she is a little unstable...her get along is ok once her get up gets her up..Your kitty’s problems may be physical and she is trying to tell you something is wrong. Get kitty well checked out, check the foods, and take a hard look at what is going on in the household...check that you have enough litter boxes one cat 2 boxs...all those sorts of things before you result to taking that last drastic action...kitty is trying to tell you something is wrong.
Marie, one last thing ... reading the first time, I did not see that you had scheduled the euthanasia for Monday. I urge you not to do it Monday, but to consult with your vet instead and try drugs instead (as outlined in my original post, or of course whatever your vet might recommend ... but I will say I have had tremendous luck calming down crazy cats with diazepam. It is a miracle drug for crazy cats!!!). If the drugs don’t help, you can always go forward with the euthanasia as originally planned, later. But your post makes it clear you will feel really guilty and sad, and feel that you have let your crazy buddy down. I urge you to give it pharmeceuticals a try first, and see if you can work this out after all. good luck!!!!!