>I will never understand these people.
perhaps it's cognitive coping during the early stages of grief. If she can convince herself it was the right thing to do regardless, then less pain at the thought of participating / helping to convince the rest of the family that it was important to do.
Similar to how the parents who have helped mutilate their own children through gender affirming procedures are now locked into a lifelong death spiral of convincing themselves they did the right thing, that it isn't just a phase of confusion their child was going through, and that others must be forced to participate in the delusion so they won't have to face the fact that they helped to mutilate their own child.