I think I can understand why her husband has kept to his view. From the first death, and for a very long time afterwards , he’d supported her wholeheartedly. Then he changed his view, with some help from others. Knowing now he was right all along to support her, having to change his view again means having to accept certain things. Firstly, that it was just purely genetics, and bad luck. And then there’s his abandonment of her.