She could have asked
Of course both made very naive assumptions. The problem is that one assumption isn't more valid than the other. But "assuming your partner isn't lying" is a risk you yourself are willing to take and that it can only hurt you, not the other. On the other hand "assuming your partner won't be bothered by X" is something that affects both of you. So, even if both are equally stupid, Hilgya was the more inconsiderate about the other's feelings. Just as Durkon was with her a couple seconds after when hedumped herbroke her heart. From my perspective, both have things to excuse about.