I started work with about 30 trainees, including “Kim”. I wasn’t active in the group chat and wasn’t really social outside of work. I had other things happening outside of work which was my priority - such as unexpected moving house. I was close to some people in the group though and was always polite at work.
Kim remained on my team for around 2 years whilst everyone else went their separate ways. Initially she made comments that I think I’m “better” than her as I didn’t “bother” with the training group socially. She would criticise my outfits for work eg asking am I not hot/cold/uncomfortable. Once, I was unwell with laryngitis but went into work and was given admin duties and she said I’ve “had a week of dossing” . She’s very competitive and would take any praise I got from others personally ie “she’s not that good, I’ve done that before” etc
We went out for a Christmas party and she was drunk to the extent she was throwing up and told me that she thinks everyone favours me. She was also explicitly telling me about another colleague’s sex life which was uncomfortable.
After this, she kept making errors at work in an area that I lead in and management asked me to investigate and resolve it, all evidenced by email. This further annoyed her as it fed into her complex although I was just doing my job.
The people I’m close with from my training group arranged a birthday outing and she wasn’t invited. She raised a formal complaint against me about this although I had no involvement. In the complaint, she also accused me of personally ruining her relationship. I have never met her boyfriend or even know who he is, but she was essentially saying he wants to break up with her due to how stressed she is.
She also ended up going to a colleague’s house and verbally abusing them during this time and gossiping about me to others. I filed a counter-complaint which was upheld and her complaint was dismissed.
She went off sick and has now returned and the atmosphere at work is awful. I’m polite to her but she’s clearly holding a grudge and treating me differently. How do I navigate this?