Christine McGuinness has confessed she blamed herself after she was raped by a classmate at a house party at the age of 13.
The 33-year-old wrote in her new book A Beautiful Nightmare — reported via The Mirror — about the attack, saying she felt guilty for not stopping the assault because she was drunk.
She said: "I took myself upstairs in a drunken stupor and got into bed. Not long after climbing under the covers while intoxicated, a boy from school came in and had sex with me, against my will.
"I remember saying ‘no’ and I tried to push him off, but I was so drunk I couldn’t physically move him."
Watch: Paddy McGuinness calls for more education around autism
McGuinness said she "blamed myself massively" after the assault, especially when a teacher and school counsellor were unsympathetic about what had happened.
"I know as an adult it wasn’t my fault, but I still think if I wasn’t drunk it wouldn’t have happened. But I’m okay, thank God," she said.
The star added: "My virginity was taken, and I didn’t get to have that special moment with my childhood sweetheart. I think he was a stupid boy who took advantage."
McGuinness also alleged she was subjected to sexual abuse by an adult close to her family between the ages of nine and 13, who would make her watch violent and sexual videos.
"I didn’t understand it or get it. He’d always talk about sex and masturbating and would take me to his house to make me watch these disturbing videos," McGuinness wrote.
She said she later heard that the man had been jailed for abusing another child.
McGuinness said her struggles as a young person have played into her decision to be "really protective" of the three daughters she shares with husband Paddy McGuinness.
All three of the couple's children are on the autism spectrum and the couple are outspoken campaigners for better education around autism.
A Beautiful Nightmare is due to be released on 25 November.
Watch: Paddy McGuinness criticises Simon Cowell's parenting skills