Originally Posted by BlackUnicorn
She's not interested in a polyship, not interested in a romantic relationship, and the two of you should accept what she says. If she's lying about her feelings, it's on her, not on the two of you.
That's good advice. I suspect however that even if my boyfriend stopped asking her to renew their relationship, she would continue to flirt with him.
He could isolate himself from her but that would mean losing some of his very best friends, who are mutual friends of hers. Unlike her, those friends are not leaving, and I think he cares more about keeping them around than he does about her.
Therefore, if we both accept what she says at face value, I think it is also prudent for us to tell her to cut it out so we can enjoy interactions with our friends without having to deal with that.