Stalker Defaming Me?

No point in making a throw away this person will find it anyway.

I am looking for advice here on what options I have, if any. Long time stalker has been making large threads containing my real name, tacking groomer allegations against me. While they're just blatantly untrue, I work with children. I fear if someone were to look me up that these threads might pop up. Is there anything I can do legally to get these taken down or take this person to court?

This person is malicious. The person once made and circulated a post claiming I was a mentally unstable black person with a gun that I planned on bringing to an event. Also untrue, and a very scary situation for me to be thrust into. I'd deeply appreciate any advice on how to handle this matter.