Oath of Rebellion by Jane Poller

Eirwyn is the darling drakin princess who just wants to escape the political upheaval the war has brought. But then her brother, the king and the most powerful drakin mage in the land, tries to have her killed.
Raised by druids with powers and abilities even they cannot explain, Knox the lumberjack is the unofficial protector of the Feral Forest. He's distracted from his work robbing the king to feed the poor when a beautiful princess begs for his help.
He tries to resist her pleas for help to defeat her brother; however, if he helps, he might finally solve the question of who he is and where he came from. When fated mates and loyalties clash, he must choose whether to save the forest, defeat her brother, or rescue the damsel!