The Scribbler (2014)

"The Scribbler" is a 2014 Thriller movie directed by John Suits and starring by Michelle Trachtenberg, Katie Cassidy. Suki is a young woman confronting her destructive mental illness using "The Siamese Burn," an experimental machine designed to eliminate multiple personalities. The closer Suki comes to being "cured," she's haunted by a thought... what if the last unwanted identity turns out to be her?