How to revoke an invitation

So we invited this old coworker because at the time she was dating a groomsman. I’ve never really disliked her or liked her. We spoke at work and we’re friendly but outside of that, not really friends. More of acquaintances. Well over the past week she has started so much crap and drama. I don’t know what I ever did to her but I do not want her at my wedding. It started with a note left in my work clip board anonymously but I’ve had several people confirm the hand writing and she just so happened to be at my work place the night the note showed up stating that my bf was smoking pot behind my back. Of course I didn’t believe it and confronted my fiancé about the letter. He quit a long time ago and told me he had only slipped up the once that I was already aware of. I knew someone was just trying to get to me. But I let it go because getting upset is what she wants. Well last night I show up for work and am approached by multiple coworkers, friends and people I don’t even know that know her asking if the rumors were true. Of course I’m still thinking it’s over the dang note. Nope! She’s now telling quite literally everybody and their momma that I walked in on my fiancé sleeping with another woman in my bed and the only reason I’m keeping quiet and continuing with the wedding is because I’m knocked up. As I told everyone yesterday if I would’ve found him cheating I most definitely would not be continuing with the wedding, he most likely wouldn’t be breathing and I sure wouldn’t still be living with him. And secondly if we’re expecting, congrats to me because we want a baby. But I’m not pregnant. I am over itttttt. My wedding is in 13 days! I have enough going on to even have to listen to it. It’s more annoying and childish than anything. I’m just tired of it all. I’m tired of being asked about it. I don’t have time for this petty crap. So how do you uninvite a guest? Bc I’m about ready say f etiquette the witch with a capital b ain’t coming and I’ll have security escort her out.