The model accused the rocker of raping, biting and whipping her during their relationship more than a decade ago in a People interview published Wednesday. An unnamed spokesperson for Manson denied Smithline's allegations to the outlet, saying her relationship with Manson lasted less than a week.
USA TODAY has reached out to Manson's attorney for comment.
"I survived a monster," Smithline told People in her first interview since she named her abuser in February. She provided the outlet with emails and messages she says came from Manson showing the two were together for more than two years.
Smithline joins actresses Evan Rachel Wood and Esmé Bianco in making serious allegations against Manson.
In late January, Wood revealed in an Instagram post that Manson had "started grooming me when I was a teenager." One week later, Bianco told New York magazine's "The Cut" that Manson's abuse "almost destroyed me and almost destroyed so many women." Bianco filed a lawsuit Friday accusing Manson of sexual assault, sexual battery and human trafficking.
Along with being sexually assaulted, Smithline also alleged Manson "cut her with a swastika emblazoned knife."
Original allegations: Evan Rachel Wood alleges Marilyn Manson used anti-Semitic language toward her
"I was brainwashed, and it makes me feel disgusting," she said about seeing the permanent mark in her thigh.
Weeks into their relationship, Smithline said Manson continued to inflict physical pain and "forced her to do a blood pact," in which she alleges he "cut me on my stomach and then drank my blood."
"The more I let him hurt me, the more I loved him and the more I was proving myself to him," she said.
She also accused Manson of locking her in a glass, soundproof room, which he called "the bad girls' room."
"If I had to pee while he was replaying one of his songs I'd heard 30,000 times, I'd have to be locked in the box," she said, adding that this happened more than 100 times.
Marilyn Manson allegations: 'Game of Thrones' star Esmé Bianco alleges abuse from Marilyn Manson 'almost destroyed me'
Smithline said she finally attempted to leave the rocker one year into the relationship, after he scolded her for becoming drowsy during a video shoot. However, she said, she continued to see him until 2013.
"I want to think that I never went back again. I wanted to go back on my terms and be in control, but it doesn't ever work like that," she said.
Smithline said she still suffers from OCD, night terrors and PTSD, but revealed her healing process started after meeting up with Wood, Bianco and other Manson accusers in September.
"Being with the other girls, these feelings of guilt and shame have lessened," Smithline said, adding that she's "not a victim."
"I'm a (expletive) survivor. I want people to know who he is, and it's worth it if not one more woman gets hurt again."
If you or someone you know may be struggling with suicidal thoughts, you can call the U.S. National Suicide Prevention Lifeline at 800-273-TALK (8255) any time day or night, or chat online.
Crisis Text Line also provides free, 24/7, confidential support via text message to people in crisis when they dial 741741.
Contributing: Hannah Yasharoff
This article originally appeared on USA TODAY: Marilyn Manson ex Ashley Morgan Smithline details alleged rape, abuse