My characters have a different outlook. Thera is a cursed land, doomed to endless cycles of violence and bloodshed. Dependant on the will of the land, which may or may not be the same as the will of the gods, victims of violence either are resurrected and mind-wiped to relive their life, or replaced by a being similar to the original.

Changes to the patterns of Thera take massive adventurer action and godly intervention.

Adventurers are elevated and damned to a more vicious cycle, keeping their memory and soul intact through death, able to see past the cycles of respawning, but capable of true death, and slowly eroding towards it.

Then again, my characters are usually at least a little crazy, so even if this is against the official explanation, it works with their psychotic point of view.