Put your cat down. Let him die with dignity. You do not know if there is any pain and if there is, you do not want him to suffer. Many times, vets will come to the house to do the euthenasia if you don't want to bring him in. You are responsible for your kitty and i know how much you love him, but sometimes we must do the most painful things to help our friends. I just put my doggy of 12 years down in December....hardest thing I ever had to do, but the right thing to do.....you will find peace with that.
My parents 16 year old cat stopped eating and it was because he had broken off his teeth and it made him miserable, lethargic and not want to eat so they pulled out some teeth and he's the best he's ever been.
If it was me I would take him to the vet to make sure he really was dying and if he is you can be there with him while the vet puts him down. My other cat got to 18 and got cancer and i took him to the vet to be put down and i held his little paw, oh so sad I'm getting teary just thinking about it.
I have a 16 year old cat too and he's getting a bit rickety in the old back legs and sways a bit when he walks but he's eating okay.
Many vets, if you voice your concerns about the animal being afraid and about wanting the pet to pass away peacefully at home, will come to your home and do it for you there. It will probably cost more, but if your vet will do it, it would be worth it to not have the cat suffer while waiting to die, and it will prevent him from being afraid in his last hour while at the vet. It's worth a phone call to see if your vet is one who will do this, and if he's not, perhaps he could recommend someone who would?
Ghilly
Lord, this is such a complicated question I don't quite know what to say.
First, I'm sorry to hear he's dying.
As to what to do... lord, that depends on your personal beliefs, and your cat's physical state.
The image of kitty passing peaceably is a nice one, but I will point out that's rarely the case. Most cats (from what I've seen) when they die, go through some form of suffering. But my view is that's a natural part of the death process. Maybe it's a rationalization on my part to deal with so much death (rescue work, here), but there you go.
If I see a cat is heading for a serious system shut down (kidney, liver, respitory issues, etc) that will lead to potentially hours of suffering, I play it safe and have it put down.
But that's me. I've had long years and many experiences in seeing cats dying (unfortunately).
And this is an older cat. The rules are somewhat different. But...
I generally take it as a sign that if kitty stops eating, drinking, AND grooming, then he is in a state of pain or being that shows he intends to die. wants, in fact, to die. Animals have the ability to "give up" and just die.
At that point, it is up to you if you want to help him on his way. Which I can't tell you to do. After all, you have to live with this decision. All I can say, is try to put your personal feelings and fears aside, and do objectively what's right for your cat.
he'll be grateful to you if you do that, no matter how it works out.