What would you do?

So there's a lady that works at our school district that hates me because she thinks I slept with her husband and I didn't and I told her this several times! We used to be neighbors. Five years ago I moved across town. And since then her and her husband have gotten a divorce. I know this because he contacted me three months ago and told me about it I told him once again I'm not interested in him. And to leave me alone because I am married and he knows this. So yesterday was the first day of school and when I went to the school Nobody gave me any eye contact or say hi to me completely gave me the silent treatment. It's a small school I know everyone.I honestly think this woman that works for the school district is using her job to get back at me. I just find it so weird that last year all the teacher and staff was treating me super nice. I would really like some advice on what you would do in the situation?