Sinéad O’Connor says that when she was 13 years old, she ran away from her mother’s home after what she describes as years of physical and sexual abuse at the hands of her mom. The Grammy Award-winning singer says she went to live with her father who sent her to a group home, from which she says she ran away as well – and ran back to her mother’s home. That’s when she says her mother finally stopped abusing her.

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“I guess I got to be the same size as her. She stopped hitting me,” O’Connor tells Dr. Phil in an exclusive interview airing Tuesday. “We developed a very good relationship between the age of 14 and 16-and-a-half. We had a great relationship because she was blown away that I forgave her.”

However, the singer says their relationship once again turned tenuous when she confronted her mom about the abuse. She says they didn’t speak for nine months and the next thing she knew, her mom was killed in a car crash.

WATCH: Sinéad O’Connor: 'I Love About My Mother That She’s Dead'

“Her life was hell. You wouldn’t want to be her,” O’Connor says in the video above. “So I was relieved for her, relieved for me, but devastated at the loss of her. She was my best friend.”

During Tuesday’s exclusive sit down with Dr. Phil, O’Connor shares her story of childhood abuse and why she says her family left her to die alone. Also, hear why she says she felt like an impostor when she rose to fame with her powerful rendition of Prince’s song “Nothing Compares 2 U.” Check here to see where you can watch.

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