It happened to my kid in a private, Christian school! Has taken years for him to “fit” in again....
Having taught in a Lutheran school, I know that bullying happens everywhere. Usually at private schools I think it’s more mental/emotional bullying than physical. A lot of times what the teachers/administrators tolerate depends on the pressure they think they’ll get from parents if they resist. If the parents themselves are bullies/manipulators they can in effect bully the teachers/administrators by threatening to pull their kid out of school or turn the other parents against those involved, if a standard of behavior is actually upheld.
At one school where I taught, I expected the students to do the required reading and take a quiz on the basic content before we discussed in class. The kids ganged up to not do the reading, knowing that their parents would say that since all the kids were having problems it must be the teacher who is the problem. And indeed the parents did exactly that - led by a mom who worked for the superintendent of the public school in town.
She said that kids will be kids but the teacher is the adult who is supposed to make everything turn out OK.
The teacher who taught the same kids a different subject (social studies) told me that he had the kids read the book during class; that’s all they did. And then they took a standardized test (intended to be taken in one sitting, closed-book), open book, over the course of 2 days, and he scaled the grades. That’s the only way he could make everything appear to be OK so the parents wouldn’t give trouble.
When the issue is bullying, sometimes one whole family is the victim of PARENTS bullying.
I’m sorry to hear what you suffered, and please tell your child that there are probably people in the school who are still hurting right along with him/her over what happened.