She's from a clan of subterfuge, so all kind of cruel behavior and clandestine plans shouldn't be any strange phenomena for her. Despite her own regrets, she might be more interested in knowing why she can remember stuff from her past life and why those memories don't match the current reality. In the older timeline, Frey was a jolly fellow, loved by the heroines, until he suddenly betrayed them and the whole mankind. But now Frey is a known scumbag loved by no one. There's quite a huge contradiction for anyone bothering to think about it.