Finch, 44, said "the biggest mistake of my life" was lying while working on the acclaimed medical drama.
"What I did was wrong," she told The Ankler in an interview published Wednesday. "Not okay. F---ed up. All the words."
Finch admitted that she "never had any form of cancer" after claiming that she had a rare form of bone cancer called chondrosarcoma, and subsequently lost a kidney and a portion of her leg. She also allegedly told her former colleagues that she had an abortion due to her chemotherapy treatments.
Additionally, Finch admitted to fabricating the story of her older brother Eric's suicide — who is still alive and working as a doctor in Florida — while employed on staff at Grey's Anatomy.
"I know it's absolutely wrong what I did," she told the outlet. "I lied and there's no excuse for it. But there's context for it. The best way I can explain it is when you experience a level of trauma, a lot of people adopt a maladaptive coping mechanism. Some people drink to hide or forget things. Drug addicts try to alter their reality. Some people cut. I lied. That was my coping and my way to feel safe and seen and heard."
Mitch Haaseth/Disney General Entertainment Content via Getty Images Krista Vernoff with Elisabeth R. Finch on the set of Grey's Anatomy during the "Silent All These Years" episode
Finch said she began to lie after injuring her knee in 2007.
"Everyone was so amazing and so wonderful leading up to all the surgeries. They were so supportive," she said of the response she received at the time. "And then I got my knee replacement. It was one hell of a recovery period and then it was dead quiet because everyone, naturally, was like, 'Yay! You're healed.'"
"But it was dead quiet," she continued. "And I had no support and went back to my old maladaptive coping mechanism — I lied and made something up because I needed support and attention and that's the way I went after it. That's where that lie started — in that silence."
Amid claims that she fabricated her medical and personal history earlier this year, Finch said she resigned from the Shondaland show and checked into a facility in Arizona before ABC Disney Television Studios could launch an investigation into her past.
Following the allegations going public in March, Finch said her wife left her and she was disowned by her family.
"I wish I had a grid that would show who's not talking to me because they can't [legally]," she said. "Who's not talking to me because they don't know what to say. Who's not talking to me because they're pissed off. And then who's sitting there waiting for me to reach out. I have no clue … it's been a very quiet, very sad time."
She continued, "There were people who, when [the] article came out, were immediately very, very nasty on text. Family and friends who called me 'a monster' and 'a fraud' and said that's all I'll ever be known for and soon, more truth would come out."
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In March, PEOPLE confirmed Finch had been placed on administrative leave from her duties on the ABC hit tied to her claims. "Only Elisabeth can speak to her personal story," a rep for Shondaland, a company founded by Grey's Anatomy creator Shonda Rhimes, told PEOPLE at the time.
Andrew B. Brettler, Finch's attorney at Lavely & Singer, also issued a statement on her behalf to PEOPLE.
"Ms. Finch is not going to discuss her private health matters," Brettler said in a statement. "Likewise, she will not speak about her pending divorce from her estranged wife, Jennifer Beyer, or comment on any statements that Ms. Beyer may have made to third parties about Ms. Finch."
Finch first joined Grey's Anatomy in 2014. While working on the acclaimed drama, she notably wrote the 2015 episode titled "Silent All These Years." The episode, which centered around a sexual assault victim, also featured her acting in the role of Nurse Elisabeth.
Previously, Finch said the storyline on Catherine Fox's (Debbie Allen) cancer battle was inspired by her own fight with the illness.
"My boss, Krista Vernoff, suggested I use my point of view as a person with cancer to write a storyline where one of our beloved characters is diagnosed, too," she wrote in an essay for ELLE in 2018.
"I was certain Catherine Fox should be the character we diagnosed with cancer — a brilliant, vibrant, sexy, 60-something, world-class surgeon — whose fire is matched only by the actress who plays her: Debbie Allen," Finch continued. "I wanted Catherine to be diagnosed with a spinal tumor similar to mine, only this time, the doctors would tell her the truth. Because she, like the rest of the world, shouldn't have it any other way."
"So I started outlining the episode with the support of an amazing writing staff, but I secretly convinced myself the episode would never air," she added. "It was the only way I knew how to write it without breaking my rule of never saying 'no' to work."
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