Mostly irrational guilt, but the feelings are still there. Or, Oh God, I was so nasty to her only two days before, if only I'd known. Or, I never said goodbye. Sometimes there are feelings of intense anger. They should have prevented this.
Someone's to blame.
You never answered my prayer. Sometimes that anger is turned inwards, and becomes depression, anger against yourself. And you feel too fed up and miserable and low and lonely to do anything. There's no purpose to life, nobody really cares, not even the family, and you wish you could pack up and die yourself. And all this may be accompanied by still not quite believing it.