I don’t like her romantically and want nothing sexual with her either. She acts desperate to talk to me, won’t get into more details.
I could act busy each time she approaches me, and avoid her as much as I can but I don’t know if I should tell my manager about this. I don’t even know what I’d tell a manager: “I’m informing that I want nothing to do with X and I’m going to keep my conversations with her to a minimum”?
Another idea: be boring as f*ck.
Do I tell her friends I don’t like her?
Ideally I could tell her directly I’m not interested / I don’t befriend coworkers (not true but it would work to soften the blow), but I simply don’t know how defensive she’s gonna get, laugh it off or accuse me of playing games.
It might be wise to talk to your boss or HR to have a written record of the situation, and ask they don’t act on it. Just in case the person is one that takes rejection really badly and goes to HR to say you sexually harassed her
Do you think they can be trusted not to take some sort of action that might take the whole situation and process out of OP’s control have a lot of unintended consequences? I feel like one’s plea that they not act upon it has a lot of risk of being overruled, or ‘act’ having some multitude of interpretations. Your suggestion makes some sense in terms of trying to get ahead of thing in case they spiral out of control for some other reason but it could result in these 3rd parties making things so much worse for everyone even if he has no ill will from the outset.