Death is an anchor, a nail driven into the fabric of reality, and the difference between ghosts and the everdying is how how deep the nail was driven
The former, formerly living folks, come back without their flesh, and with some degree of their memory and existence intact. To what degree determines how they interact with the world. Deeper driven, they can be reasoned with, to some degree. Forces play against them over time, wiggling the nail until it breaks or comes loose entirely; removing their minds or even any manifestation.
The everdying on the other hand, come back intact, and mostly unchanging. They are in many ways fixed by their moment of death, and it takes a great will to reshape them past it. Truly they require a great will to remain, as the same forces pull at them, wiggling them out of their intrusion into the fabric.
While we refer to them as the everdying, they exist in a state that most would consider to be immortal; not strictly true, but true enough over the lifetime of most mortals. Everdying will recover from any injury, as they will leap back to that state they were pinned to, whole and remade, only slightly frayed at the edges. Where they return depends on the nature of the destruction and their awareness of it. A simple stab wound, they’ll shrug it off without much notice beyond the pain. A gunshot somewhere fatal, they’ll pop back up a few minutes later, often exclaiming how lucky they were to have simply been knocked unconscious. Something more devastating, something that destroys the flesh, and they’ll recover in the place they died, as they died; Same clothing, same flesh. That’s when most realize that they are everdying. Prior to that first significant death, they think themselves merely lucky, or in some cases unlucky; denial is a powerful thing, in it’s own way.