Demi Moore Says She 'Blinded' Herself from Her Own Pain After Ashton Kutcher Split: 'I Lost Me'

Demi Moore is opening up about her past struggle to cope after the end of her marriage to Ashton Kutcher.

In her upcoming memoir Inside Out, the 56-year-old actress reveals how she picked herself up after her life began to unravel when she and Kutcher decided to go their separate ways seven years ago.

“I lost me,” Moore told Diane Sawyer, in an interview about her book that aired on Monday’s Good Morning America. “I think the thing if I were to look back, I would say I blinded myself and I lost myself.”

Moore and Kutcher began dating in 2003 after meeting at a dinner with mutual friends and were married from 2005-2013. They separated in 2011, in the midst of reports that Kutcher cheated on Moore, and eventually divorced in 2013.

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According to GMA, Moore writes in her book that the deterioration of her relationship took a horrible toll on her mental and physical health.

Coping through the pain, the star broke her 20-year sobriety and began abusing substances like Vicodin and alcohol. Her three daughters — Rumer Willis, 31, Scout Willis, 28, and Tallulah Willis, 25 — stopped speaking to her. And her former husband and friend, Bruce Willis, pulled away as well.

Isolated and in anguish, she weighed just 102 lbs. Then in 2012, the star was rushed to the hospital after smoking synthetic marijuana and inhaling nitrous oxide at a party.

“I guess the fundamental question that came forward for me was, ‘How did I get here?’ ” Moore told GMA, reflecting back on it all. “From where I started to what I’ve experienced, where I’ve been, how did I get here?”

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Much of Moore’s pain stems from her troubling childhood, which she characterized to GMA as “colorful.”

In her book, the actress talks about her days growing up, explaining that both of her parents battled alcoholism and raised Moore in an environment filled with infidelities and thunderous fights, GMA reported.

She later learned that the man she loved as her father was not her biological father. “I made up about that — that I wasn’t wanted or that I don’t deserve to be here,” she explained.

After he left, Moore found herself responsible for her mother’s well-being, which proved to be a challenge.

The Ghost actress was 12 when her mother first attempted suicide and recalls in her memoir, using her fingers to dig the pills her mother had swallowed out of her mouth. But this was just one of “many, many times” she’d stop her mother from potential death by suicide.

“[My childhood] was done,” Moore said. “[It was a] life-changing moment.”

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At the age of 15, Moore was raped by a man who she said told her, “How does it feel to be whored by your mother for $500?”

When asked by Sawyer if she thinks her mother sold her, the actress said “no.”

“In my deep heart, I don’t think it was a straightforward transaction,” Moore explained. “But she still did give him the access and put me in harms way.”

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In her darkest times, Moore found the courage to try her hand at acting.

Despite having no training, she found success — first, at 19, on General Hospital and years later, at 23, in her breakout role in St. Elmo’s Fire.

“I was figuring it out by the seat of my pants. The school of ‘fake it til you make it,’ ” she said. “I think it was more, the confidence was, ‘I don’t have anything to lose. I don’t have anything to lose, I don’t have anything. So why not?’ “

To tame her fear, Moore turned to alcohol and cocaine. “I don’t have an off switch. I don’t have the thing that says, ‘This is enough,'” she recalled.

Eventually, the young star went to rehab, which she called “a profound gift.”

Twenty years later, Moore met Kutcher. “I just felt like a 15 year old girl, hoping somebody liked me,” she confessed.

The second part of Moore’s GMA interview will air on Tuesday — the same day her memoir, Inside Out, hits stores.