Olivia Newton-John is getting candid about her past battle with breast cancer.

“I am grateful for the experience because without it I would not have done many of the things I have done in my life. It’s taught me compassion for those going through difficult times,” the 68-year-old Grease star revealed in a new interview.

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Olivia was diagnosed with breast cancer in 1992 and underwent a mastectomy shortly thereafter. “I felt complete and utter dread [about having the surgery]. One night, shortly after it had been confirmed that I needed a mastectomy, I couldn’t sleep,” she recently told the Radio Times.

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Olivia with her Grease co-star John Travolta in 1992.

“I went downstairs, sat in the dark and felt the fear washing over me. I was convinced that the cancer had spread at top speed and was in every part of my body,” the Australian singer continued.

“For a few weeks my world was in turmoil, but then I calmed down and started to fight back mentally. Deep down, there was always a tiny nugget of hope inside me that said, ‘You’ll be OK. You’ll make it,’ and that little voice kept me going,” Olivia said of battling the disease nearly 25 years ago.

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Thankfully, the actress beat breast cancer and has since become an impassioned advocate for health awareness and cancer research. “After I had my treatment, I had counseling, which helped me to think about the importance of my feelings,” she said in a 2009 interview.

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Olivia (center) at a breast cancer awareness event in 2014.

“Having cancer forced me to think deeply about myself for the first time, so it was a positive experience in that respect. I learned not to feel guilty about my successful music career,” Olivia continued. “I also realized you had to eat well, exercise and be happy. It sounds obvious today, but I fully credit that attitude with my good health.”

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“Today, I still eat well, using organic food where possible. I have been a vegetarian, but I’ll now have grilled chicken or fish. I believe in treating yourself, so I drink the odd glass of wine and I like chocolate. I play tennis three times a week and I get out into the fresh air every day,” she added.

Click through the gallery below to see more stars who have bravely battled breast cancer!