From what I played there were multiple opportunities to rebuff or criticize the guys.
With Ian specifically I remember you can be bored of his long-windedness, openly suspicious that he's doing so on purpose, or angry because you're sure he's doing it on purpose. Or civil, because maybe he's actually going somewhere with his rambling.
I also remember having the choice to not humor most of the advances because I already had a guy in mind. And apparently we'll be getting more ways to react.
I think the love trope works well due to it preventing them from swarming her like a bunch of piranhas. Because they tried exactly that. And now that she's aware just want something from her, it's no longer viable to just be the one that flatters her the most.
If it were something tangible like her "eat her heart" or "take her virginity" then I wouldn't put it past them to turn into absolute animals to be the one that gets it from her whether she consents or not.
Even if it were something intangible like "she knows where (special item) is" or "she can sense the presence of Altids" then they could easily threaten to throw her to the wolves, starve her, or harm her if she doesn't help.
Getting her to genuinely love them is the one thing they can't force, and their shortcut of tricking her into falling in love is gone now that Vincent spilled the beans.
I'd say that the "none of them would even look at her" comment sounded believable from Vincent at the time BECAUSE of how inappropriate and suspiciously forward they were all being. It's at least one of the only things she's been hearing that makes the most sense, since Ian had been making absolutely none. It can't be chalked up as a quansie thing either, since Cass wasn't acting a fool. Nor Ian or Vincent.