Never date a co-worker

I know, that seems obvious to most 🤣 it used to be one of my biggest rules but earlier last year, I decided to take a chance on a new co-worker, she was very beautiful and fun to be around. Long story short it didn't work out. I didn't really try hard enough in the relationship, she has her own issues and we parted ways. The problem is, we both still work there. I have to see her everyday and it's turned into something extremely toxic I keep finding myself in dreams I'm want no part of. She's been trying to manipulate me by being rude or snobby to me some days but throwing in a day where it's like we're best friends again. She throws my name under the bus and says bad things or often straight up lies about me. Then she tells me that people told her I've been talking smack about her but when I ask other people, they obviously have no idea what I'm talking about and I look like an idiot. When really I just want to have a peaceful day at work and not think about it anymore. Anyways, if I've kept your attention this long, thank you for reading 😁 I hope your day is going better than mine and thanks for listening to me vent about how dumb I can be sometimes 🤣