In a bullying situation there are plenty of opportunities for hurt feelings -- even the bully's and their supporters'.
When a bully says they are "through with you", either in person or through someone else such as an Administrator, is it surprising that the target of the bullying behavior is also "through with" the bully?
It shouldn't be a surprise to bullies when their target ignores them when they walk down the hallway, or when they look away and pretend they don't see them, or when their target never looks in their direction in meetings. Unfortunately, bullies typically react badly when they are treated as they have already treated their targets -- it turns out that they don't like it any more than their targets do.
Unfortunately, the bully may take offense and uses the target's reactions to justify their continued bullying behavior.
Even if the bully recognizes their own behavior, which is not likely, the bully hates their target even more for making the bully recognize themselves and not liking what they see -- which is why a bully will rarely apologize for their behavior. It's too threatening to their self-image. Bullies don't see themselves as bullies. They think they are strong women, or men upholding standards. Their self-delusion is critical to their sense of self.
"Our prime purpose in this life is to help others. And if you can't help them, at least don't hurt them." - Dalai Lama
During the pain of being bullied, even the targets of bullies fall short of that idea sometimes...
"Nothing is so easy as to deceive ones self. What we wish for, we readily believe." —Demosthenes