i am a little confused about this and i am thinking some folks may be confusing day care/preschool with drop in community center care. i am going to state my assumptions please correct me.
This women who has offended is teaching classes at a community center and drops her kid into the same care group as your son when she is teaching a class, right?
She is not a day care teacher, right?
your interface is when your kids are in the same group, right?
so why not change the time you have your kid there to be opposite of her classes. or put you kid in a different group (older?)
why should you give up what seems like a great community center because of one woman.
and it seems like you are more affected by this woman than your son is.
It also seems some of the comments from folks here are based on the assumption that she is a professional day care or preschool worker and is being unprofessional based on that.
what kind of classes does she teach at the community center?
have you asked your son why he will not say hi to her? maybe it is a strange reason, she smells differnt or the pitch of her voice gives him a headache. His perceptions may not be the same as yours.
as far as expecting behavior that is unpleasant. I have found expecting it to be protective. I expect it to happen sometimes. I dont let it ruin my expeience of a place and i assign the problem to the one doing it, not to everyone else of that place. sometime i tolerate it. sometimes i call people on it. It depends on what the situation is worth and how it will affect my kid in the long run. sometimes i let it go because its just not worth the drama to confront it and doing so wont improve things for anyone involved. but sometimes it is important to empower my dd to stick up for herself. it varies.
but if you leave the community center, she wins, and you son may not even have any awareness of this lady since he ignores her. the teacher ignored the woman too. that should tell you something. what is your evidence that they are friends? would she ignore her friend when a 2 yo disses her? or would she intervene to help her save face.
I may be totally off here, but there could be a different interpretation to all this.