about the darkness

what if death, unlike what many believe it to be, was actually an entity. when we 'die', we combine with this entity, for the rest of our lives, living in an alternate reality, where we never died. but then again, at the moment of death, there would be a fair number who would be in a weakened state, or in great pain, knowing that they will die. how would they be in their alternate reality? would they carry on the pain in that reality?