She’s best known for being a pop superstar and playing Sandy in 1978’s big-screen version of Grease, but Olivia Newton-John has another job these days: warrior. “My dream is to see an end to cancer in my lifetime,” the star, 70, previously said on Instagram, and has said, “I’m winning for the third time. I feel great and positive.”

After an initial breast cancer diagnosis in 1992, Olivia received a mastectomy and treatment. Then in 2013, she underwent more therapy after the disease spread to her shoulder.

Given a clean bill of health, she was on tour last year when she began suffering severe back pain. “I would limp backstage and gingerly lie down on my dressing-room floor, crying in agony,” she wrote in her new book, Don’t Stop Believin’. An MRI revealed a recurrence of her cancer, which had metastasized into her lower back.

The star admits she had some dark days after the diagnosis, but she feels good about her progress. “I believe I will win over it, and that’s my goal,” Olivia previously said on Australia’s Sunday Night. She also founded the Olivia Newton-John Cancer Wellness & Research Centre in Melbourne, Australia.

Olivia has been treated with radiation and now uses herbal therapies, including cannabis oil, to manage pain. “Cancer is something I will need to stay on top of. It’s up to me to manage my stress, to eat and rest well and to continue with the healing protocols,” Olivia wrote. “I truly believe this will be my final round with cancer. I will go on with my life.”

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Olivia can always rely on her husband, John Easterling, to help lift her spirits too. She previously said on Facebook that John has been the perfect spouse. “My husband John is taking great care of me and I want to thank all my family, friends and fans for their concern, love, support and good wishes,” she said. “I look forward to returning to performing soon!”

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