I could see Kurogane picking up that attitude during his early days around them; it would be something he needed to believe, that fit in with what his Father had taught him but was more suited to the harshness and unfairness of his life now; If I become strong, nothing else will matter. If I'm strong, I can do anything.

She probably doesn't know exatly who the culprit is, but she may suspect that it's someone from another dimension. She has the same powers as Kurogane's mother afterall, and she's heard Kurogane's description of what happened, so she may have been able to figure out the means. Which would suggest a 'who.'