Revenant. The Revenant Chronicles, #2

It's been six long years since Mackenzie Bright Runner lost her lover, Elijah Riemer, to the Revenant Virus and her Revenant protector, Ren Leonard, to a crossbow. Mackenzie has returned to the Stronghold, ousted its corrupt dictatorship, and brought peace and freedom to her beloved settlement. Things are running as smoothly as they can in a post-apocalyptic world infested with savage monsters. Until a group of her people traveling between the Stronghold and the San Juan Islands is slaughtered to a man.
The sole survivor fingers the Father of the Apolcalypse just before dying. Mackenzie knows that Ren Leonard is dead; he took a crossbow bolt to his heart before her very eyes. But she can't forget that his body was never recovered. And while they all heard the shot that supposedly claimed Elijah Riemer's life before he succumbed to the Revenant Virus, his body was never found, either. When her foraging team begins finding helpful solar devices in areas where Mackenzie just happens to be, she starts to doubt everything she thought she knew, for the devices point straight toward Ren Leonard.
But the murders point toward someone with a vendetta, someone who would have every reason to harbor a burning hatred for her. Someone who became infected because of her. Elijah Riemer.