Reluctant Enemies

Beth Astria is just a normal girl.
That's what she believes and lives by.
Until her parents take her to a castle far from their old home and forbid her to speak to or even look at the handsome stranger who was kind to her.
Now her life is being turned upside down and her siblings are getting dragged into the storm alongside her. Why do her parent seem to know so much about this? Why are they letting everyone get hurt?