So, they're not exactly removing Five's curse: he ingested a small fraction of the emotional absorption ability of a cursed mirror. He can only 'absorb' so much before he 'fills up.' Five's healing options are to basically either just have the healers 'empty him' (but he'd still 'fill up' later) or, riskier, 'empty him' and remove the mirror ability, which the necromancers would like to keep. That wouldn't break the curse, more like transfer it. No one can outright break that curse.

That said, Wrath can start picking up general curse breaking: the first step would be curse containment, meaning... you've guessed it, time to look at wards. Oh, what fun that will be.

Re: afterlife/souls — Taravast is a bit of a blending cauldron of foreign and local mores, so you could expect a diversity of takes on what happens after you breathe your last: from various divinities believed to take your soul under their stewardship, to reincarnation theories, and notions that man only has one life before becoming one with the earth, or even denials that the soul exists.