Cold as Hell by Kelley Armstrong

Haven’s Rock is a sanctuary town hidden deep in the Yukon for those who need to disappear from the regular world. Detective Casey Duncan and her husband, Sheriff Eric Dalton, are starting a family now that they’ve settled into their life here. As Casey nears the end of her pregnancy, she lets nothing, including her worried husband, stop her from investigating what happens in the forbidden forest outside the town of Haven’s Rock.
When one of the town’s residents is drugged and wanders too close to the edge of town, she’s dragged into the woods kicking and screaming. She’s saved in the nick of time, but the women of the town are alarmed. Casey and Eric investigate the assault just as a snowstorm hits Haven’s Rock, covering the forest. It’s there they find a frozen body, naked in the snow. With mixed accounts of the woman’s last movements, the two begin to question who they can trust—and who they can’t—in their seemingly safe haven.