Brave the Night by Cassandra Moore

The Bully Boys are the only defense Coyote Trail has. Part bikers, part paladins, the modern-day wolf pack on wheels is dedicated to protecting humans from the swarms of savage shapeshifters who roam the deserts. Called Ferals, these once-human abominations threaten to inflict any pockets of civilization with a highly virulent plague turns good people into mutated beasts mutated abominations.
Shane Lawson, alpha werewolf of the Bully Boys pack, has sworn to avoid love as much as he’d avoid the Beast Plague itself. The worldwide epidemic has already cost him everything he held dear – his lover, his best friend, and his brother. Better to run himself into the ground eradicating Ferals than to chance another scar on his already battered heart.
Mechanic Erin Calloway left the relative safety of the Midwest to find a new life in Coyote Trail. The Bully Boys need a solid wrench to keep their rides in Feral-hunting order, and Erin needs a fresh start to drive away the ghosts of tragedy that haunt her. She expects ridiculous temperatures and herds of cactus. She could never foresee a gorgeous werewolf with broad shoulders and familiar ghosts to plague him.
Her sunny humor and soulful strength make Shane want to violate his vow and put his heart on the line. His deep integrity and wolf’s bravery challenge her to reach for a love she’s never felt before. But when the plague that threatens civilization hits too close to home, Shane and Erin must both fight to save what matters to them most – each other.