@TheBlueCat
Sorry if you took offense from my comment. I didn't have any intention to insult you, just that vague memory could happen to everyone.
But now I think you're misunderstanding some part of plot rather than incorrectly recall. She is not hate, disgusting at, not have any bad feeling with the empire, except that she fear that her past life might be exposed and empire might punish her. Other than that I'd say she still have value of imperial citizen at the core, thus it is not surprising at all that she was swayed by a man from the empire.
In fact, after thinking about it, this is more reasonable than being swayed by her current country's men, as her value still be of empire's and quite contrasting to her current kingdom's.
You can say that she is overthinking and too paranoid, but don't have enough courage to take more decisive action on her own. They're rare, but few people in RL are like that. Just think of it as her unique shenanigan.