Dear Annie: My best friend, “Ashley,” and I have worked at the same marketing agency for three years. We started on the same day, bonded over bad coffee, and we have been inseparable ever since. We have lunch together almost every day and text constantly. We have even taken a few vacations together. She was the first person I told when I found out I was pregnant last year, before I’d even told my mother.

Last month, I was promoted to Senior Manager, which means I am now directly responsible for overseeing her work, giving her performance reviews, and if it ever came to it, disciplinary action. HR made it very clear that I needed to “maintain professional boundaries,” which I understood in theory. But I didn’t expect how quickly things would shift.