The traitor by Anthony Ryan

It’s been a long journey for Alwyn Scribe. Born a bastard and raised an outlaw, he’s now a knight and the most trusted advisor to Lady Evadine Courlain. Together they’ve won countless battles and helped to bring order to a fractured kingdom. Yet Evadine is not the woman Alwyn once knew. As puritanical fury increasingly replaces her benevolent faith, Alwyn begins to question what her true motives really are. As the kingdom braces itself for one final battle, Alwyn’s conscience fights its own war with his heart. Now, more than ever, he must decide whose side he’s really on.