This is such an artfully done psychological horror novel that though I felt like reading it in one go, I had to periodically put it down. It's a spine-tingling, horrifying, moving, emotional ride. Even when I thought I knew what was going on, the novel took me to a different place (do not peek at the afterword, you will be spoiled!). Catriona Ward is definitely a must-read horror writer.
The Last House on Needless Street, by Catriona Ward