I have a very difficult colleague, I am management, she is not. She has constantly undermined me and made the office atmosphere very toxic. This has been going on for 2 years now. HR have been trying to manage out of the business for a while now but she is clever enough to go as far as the line without crossing it. Yesterday she contradicted me at a whole company meeting and accused me of lying. I have full support of management and have documented proof that she is wrong. she continued throughout the day and went to many people in the company accusing me of lying. Management witnessed this and advised me to make an official complaint As we speak she is now in a meeting with HR who will present her with a written warning. I have moved myself to another office it the building but i will be alone with her for the remainder of the day and I am almost sick with worry over it. Any advice on how to manage this situation? Thanks