Not everyone reacts the same way to the same news.
Chapter 6: Adrastea looked at her mother, whose hazel eyes burned with a desire to know.
Tell five different people the same news and they'll react five different ways. Just because you might consider something horrific doesn't mean someone else might not express morbid curiosity.
Everyone's world view is different, even people who were raised in the same village. Adrastea's shared her dilemma with the four people closest to her. Each one reacted differently, and each have offered their version of advice, some of it possibly contrary. The one thing they are united on is that they must stand together against Mor-Lath.
The whys behind their unity are not the same.