Brothersong : Green Creek book four

"In the ruins of Caswell, Maine, Carter Bennett learned the truth of what had been right in front of him the entire time. And then it--he--was gone. Desperate for answers, Carter takes to the road, leaving family and the safety of his pack behind, all in the name of a man he only knows as a feral wolf. But therein lies the danger: wolves are pack animals, and the longer Carter is on his own, the more his mind slips toward the endless void of Omeg...