"Our love for each other transcends our understanding."

Olivia Newton-John's husband, John Easterling, has penned a heartfelt tribute to the star following her death at the age of 73

The singer and actress, who was largely known for her iconic portrayal of Sandy in the 1978 film version of the musical Grease, died Monday, and now Easterling is celebrating her life.

"Our love for each other transcends our understanding. Every day we expressed our gratitude for this love that could be so deep, so real, so natural," Easterling wrote on Instagram. "We never had to 'work' on it. We were in awe of this great mystery and accepted the experience of our love as past, present, and forever."

He added, "At Olivia's deepest essence she was a healer using her mediums of song, of words, of touch. She was the most courageous woman I've ever known."

Despite his grief, Easterling concluded on an uplifting note, writing: "Even now as her soul soars, the pain and holes in my heart are healed with the joy of her love and the light that shines forward."

He also thanked those who have sent kind words since the news broke. "Our family deeply appreciates the vast ocean of love and support that has come our way," he wrote.

John Easterling (L) and singer Olivia Newton-John (R) attend the 50th annual CMA Awards at the Bridgestone Arena on November 2, 2016 in Nashville, Tennessee
John Easterling with his late wife, singer and actress Olivia Newton-John
| Credit: John Shearer/WireImage

The pair married in 2008. Though they first met in the early '90s, their relationship didn't begin until 15 years later. Newton-John and Easterling, an entrepreneur in the natural health business, bonded over their passion for holistic aids. In 2019, the performer told PEOPLE that her husband helped her manage her cancer symptoms with medicinal marijuana he grew himself.

Newton-John battled breast cancer for 30 years, and following the news of her death many of her former collaborators — including her Grease costar John Travolta, Rebel Wilson, and Mariah Carey — celebrated her life.

"My dearest Olivia, you made all of our lives so much better," Travolta wrote on Instagram. "Your impact was incredible. I love you so much. We will see you down the road and we will all be together again."

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