Or actually continually losing it by being in a place of falsehood.

The self actualization of all of mans biased knowledge, ideals and half truths and moralities is what you call hell.

Because by being away from truth or god your being isn't "fed" so like a plant away from water and sun it starts withering and starving. It's not just a loss and then pain of that loss, but the continual loss of not living in god but a world made of your own mental creations, which can be incredibly biased relative to truth of being.

So that pain of being in a sort of no mans land and losing being as it happens, as you see "what could have been" is what you can call "hell"

Which mentally can seem eternal even if the soul doesn't cease to exist. Just a longer path toward truth.