Doesn't happen. She knows how crazy he is because he wielded her she was a sword, so she's had pricey to his thoughts back then. That's why she chose to support him, so that she could have her revenge.
*against the emperor not the prince.
I think he is crazier than how he was in the past since he has no problem killing families now. I doubt he was as crazy as he is now, even by her standards. and I kinda disagree, she choose him cause he was easy to make him do what she wants, he is an easy doll to use. not cause he is crazy, it seem like she mostly ignore the "crazy" part and his feelings too, since she is kinda of dumb right now when it come to human emotions.
I think you need to read this again. She chose him because he is crazy. He was a tyrant. He was also the most powerful person to wield her as a sword. She chose him because he destroys everything. Now the last time I checked, tyrants didn't exclude entire families from the term "everything" she has just been training and educating him to get to this point. She doesn't care about what he does as long as he destroys everything.
Can't wait until Charlize realizes he is crazier then what she sign up for and get scared (⌒▽⌒)