Wildflower Hearth by Moira Ashe

After the death of his fiancée, Liam Garner and his dog move to the small town of Grange, Louisiana, where a religious group, Wildflower Hearth, seems to have much of the town under its thumb. Drawn to one of its members, Liam decides to join the group, but soon discovers that it's not as innocent as it seems. When strange things start happening around town, Liam struggles to keep his own sanity. From sentient Spanish moss to Rougarou attacks, Liam is pushed to his mental limits as he tries to find a way to stop the madness before it's too late.