What happens when Ismae's husband discovers her lineage in the novel, Grave Mercy: His Fair Assassin, Book I?

At seventeen, Ismae is sold to a man in an arranged marriage. When her husband realizes her lineage, he beats her badly and threatens to turn her over to the church. Ismae is saved by the hedge priest who married the two and spirited away to the convent of St. Mortain where she learns the art of assassination.