Tl;dr – Title says it all
I developed a strong interest in an attractive woman that works in another part of my office building. I didn't talk to her because we're colleagues. However, her friends pressured me into talking to her and we got along instantly. The more I got to know her, the more I was unsure that we'd be a good fit. Her friends still pressed me (somewhat uncomfortably), so I kept talking to her.
Eventually I confessed my crush after like a month and a half and she rejected me HARD. I told her I was nervous around her because of a crush. She proceeded to tell me that she has a man, that I was being inappropriate, and me being nervous made her uncomfortable. I apologized and we agreed that her I would not talk to her anymore. It stung, but I moved on pretty quick.
However, despite me moving on and ignoring her, both her and her friends still keep following me around the office (even to the bathroom), watching what I do, she keeps walking past/hanging around my desk, staring directly at me etc. She even got really pissed at me because I started ignoring her for other people.
She also tried talking to me despite us agreeing not to speak anymore because I made her uncomfortable. Now, I learned that she managed to get some of the other women that I'm cool with (in the office) to stop talking to me, but of course her friends are still keeping an eye on me.
All of this is unprompted. I've only talked to her like twice in the past week and that was only because her friends wouldn't leave me alone, and I'm actively showing interest in other women.