Rogue Familiar by Jeffe Kennedy

He left to save her from herself… But who will save him from her?

When Lady Seliah Phel wakes from a drugged sleep to find herself abandoned by her newly bonded wizard, she vows revenge—and to hunt him down. Tracking him through the familiar wilds of the marshlands of her home is the easy part; learning to use her nascent magical skills is something else entirely. So is facing the vast, uncaring society of the Convocation in a time of brewing war.
Jadren El-Adrel is not known for doing the right thing, but getting as far away from Seliah as possible before he drains her dry will be his one noble gesture. So what if she weeps a few tears. Better than her dying in his service—or enabling him to become the ravenous beast that crawls beneath his skin. Unfortunately, in his self-imposed exile, and without the power of his familiar, Jadren quickly runs afoul of the enemy.
As her vengeful quest for recapture becomes a rescue mission, Selly faces all she still doesn’t know about the greater world of wizards and familiars. And Jadren, once determined to walk his own path and stay far, far away from the idealistic fools of House Phel, finds himself aligning with them against the house of his birth. War is coming to the Convocation, which means a clever wizard should pick the side most likely to win.

Sadly, Jadren has never been all that clever…