Ok - my recall is very very vague but I do remember really enjoying it!
Its a thriller/murder type plot, with a medical connection. The main character is a woman, possibly a doctor or nurse. There’s another main character who could be a policeman (or a vet?).
Main character lives in a house in the woods or in a similarly remote location. The book is set in America or Canada.
That’s all I can give you to go on!