My coworker refuses to treat their lice

Hello!

For context, I work at a school… SO, back in October my coworker told me she and her family had been “battling lice” for over a month. She told me this after weeks of being close contact with me in meetings and socially. Upon checking my head, I discovered I had lice. I immediately went and had it professionally treated and removed (which cost me hundreds of dollars). I followed all the recommendations about cleaning out my personal belongings and home to ensure I wouldn’t become reinfected. I also went for the follow up at the lice treatment center to be certain I was all clear. My coworker also went to this treatment center but continued to tell me for weeks that she and her family were still battling lice. She’s stopped updating me on the situation but never told me that she and her family were lice free. I’ve been extremely proactive since the initial discovery of lice. I’ve since worn my hair up every day, which she’s mocked me for, done near daily checks and worn sprays that are lice deterrents. At times I thought I was just being paranoid, but I can confirm today that I still saw lice/knits in her hair. A lot. What should I do?