AS, I think your focus is misguided.
Ignore this woman. She's a cipher. She is a tool with which, if you remain silent and observe, you can learn important things about your boyfriend.
If your boyfriend responds to her, HE is the problem... not her. Dump him and find someone more loyal.
If he doesn't respond to her, then you have no problem. Right?
Miyah wrote:
AS,
what you need to do is tell your boyfriend that you feel that this women is trouble and she's trying to steal him away. In addition, explain the examples such as with the napkin and her evil plan. I would also advise him to go to this so-called, "get together" which is really just a way for her to act like Scarlett O'Hara. I also advise you to politely and assertively tell this women that you know that she likes him and that she's jealous, but he's already been committed to you. You may also advise her that he isn't right for her and that she shouldn't make things happen that aren't supposed too.
I must respectfully and entirely disagree.
If you react in this way, you will be according this woman far more importance than she deserves, as well as making yourself look needy, insecure, and grasping.
Quiet confidence is much more effective in these situations. This state of mind can be achieved by remembering that relationships are like buses: if you miss one, another will be along in fifteen minutes to half an hour.