Her face speaks of many emotions as she watches her father been taken away by the guards. It wasn't a surprise, they had expected this will happen when the prince came to them last night.
He asked them some questions, and she informed him about Simon calling off the engagement, and how Imogen slapped her. And when he was leaving, he told them this.
This will be their last moment as father and daughter, at that moment she realizes that her father's crime has been made known to the world, and she was the reason it happened.
She was so obsessed with her love for Simon and failed to see she fall for a monster. And now her father will be killed for her crime.
At least, she will get what she always wanted, getting married to Simon. But now, she doesn't want that, all she needs right now is her father.
Not the stupid marriage, not Simon that never loved her. However it is too late, she ruined everything.