Hunting the Witch by Ellen Hart

Slowly recovering from a head injury gained after a run-in with a killer, Jane Lawless is working a limited schedule at her restaurant, the Lyme House. Meanwhile Dr. Julia Martinsen, Jane's former lover, wants to rekindle their relationship. Jane is reluctant, not because she doubts her own or Julia's feelings, but because she feels Julia is keeping one too many secrets from Jane. When a man is murdered, Jane's suspicions are confirmed by Julia's strange reaction. Partly to discover what her lover is hiding and partly out of fear for Julia's safety, Jane reluctantly resumes the role of sleuth, teaming up with her good friend and partner-in-investigation, Cordelia Thorn.