The Skull Ring by Scott Nicholson

Julia Stone will remember, even if it kills her. Dr. Pamela Forrest is determined to bring Julia's memories to the surface, hoping to heal Julia's panic disorder. The therapist keeps returning Julia to a night twenty-three years ago when Julia was four. A night of hooded figures, strange chants, pain, and blood. The night her father disappeared from the face of the earth. Julia rebuilds the past a piece at a time during the mind-wrenching therapy sessions. But the line between the past and the present begins to blur. Julia finds a silver skull ring that bears the name "Judas Stone." The same ring had been worn by one of the hooded figures who scarred her both mentally and physically on that long-ago night. Someone is leaving strange messages inside her house, even though the door is locked. The handyman, who has a key, spends a lot of time in the woods behind her house. Her boyfriend Mitchell becomes distant and violent. And the cop who investigated her father's disappearance has followed her to the small Appalachian town of Elkwood. Now she has a head full of memories, but she doesn't know which are real and which are the creations of Dr. Forrest. The shadows of Julia's panic are growing larger and darker. But succumbing to madness seems safer than heeding the whispers that claim ownership of her body and soul.