Is the divorcing two way? Like the princess can also divorce the prince first. If so then the Ml is stupidly trying too hard to make the princess hate him.
Now, it's their turn to protect her. I was wondering why she didn't pretend to be her own daughter. At least that would explain her appearance more. That way it would feel too weird for the disciples to be spoiled by her younger self and instead would spoil her instead. Oh well, guess it works...
This guy no different from the empress, once you annoy them, they don't mind killing you off. He seem to be fine knowing that she died. death is probably normal to them, yike.