Sneaking away to die?

I believe Mr. Man, my 17-year-old ginger tabby, has done this. :(

He's been strictly an outdoor kitty for 15 years or more. He didn't want to come in (probably because of the dogs, though I invited him in on more than one occasion, even when the dogs were put away). He showed up faithfully every morning and evening to my house and/or the next-door neighbor's for meals, and ate quite heartily. In the winter, he stayed in my basement, which had a door he cold get in and out of.

When I was a kid, my neighbor found our older cat, who'd gone next door to die under a bush.

I have been looking for Mr. Man in all the neighbor's yards and down in the woods behind the house, as well as the basement. The woods are vast, and very overgrown, so I might never find him.

He never went back there as far as I know, but when they are going away for this, maybe they want to go farther?

The last time I saw him was last Sunday, the 26th, for dinner. He was getting weaker, but still eating very well and actually BAR. He's a friendly kitty, not feral or anything.

He's "gone missing" a few times before, but never for this long--which is why I suspect the worst.

I absoutely know that this is one of the risks of having outdoor kitties (which I will never do again). I always thought of him as a pretty smart cat, because he lived so long as an outdoor cat. He rarely crossed the street, and rarely went further than 1 or 2 houses. There are never any loose dogs in the neighborhood, and he occasionally scrapped with neighbor cats, but nothing serious.

I knew the end was coming, and if he went away and died somewhat peacefully, I am OK with that. But I'd like to know, and to find him so I could bury him properly. I also want to find him so I can know if he suffered or not. :cry:

It got me to wondering: do they go to a familiar place when they go away to die? Or do they choose a place further away? Why? Are cats different from dogs in this way? If a dog is left to its own devices, will it choose to die close to the pack, or not?