After about a year of dating, Sag Harbor supermodel Christie Brinkley and singer-songwriter John Mellencamp have broken up.

“Both the mileage between their homes and their heavy career demands interfered with their ability to maintain the relationship,” a representative for both Brinkley, 62, and Mellencamp, 64, told People magazine Tuesday, adding, “They vowed to remain best of friends.”

Brinkley, an ex-wife of Billy Joel, has been promoting her new line of prosecco while Grammy Award-winner Mellencamp was on his 2016 Plain Spoken Tour, throughout most of April, including four dates in Manhattan though none on Long Island. He resumes the tour in October, following a Farm Aid benefit next month.

In a recent interview with People, Brinkley recalled meeting Mellencamp at a Hamptons party in 2015. “I thought, ‘Oh my gosh, we’re really opposites. He’s kind of a throwback from another time, like a silent cowboy.’ But then we talked and realized that we do have a lot of shared interests.”

One of them, she told the magazine, was being parents and, in Mellencamp’s case, a grandparent. Brinkley has three children: Alexa Ray Joel, 30, with second husband Joel and Jack Paris Brinkley Cook, 21, and Sailor Lee Brinkley Cook, 18, with her fourth husband, architect Peter Cook, whom she divorced in 2008 after 12 years of marriage.

Mellencamp has five children from three marriages, and six grandchildren.

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“John and I are two people that have very full lives,” Brinkley said in the People interview. “We’re just trying to enjoy each other when we can see each other and try not to put too much on it.”

On Sunday, Brinkley and her two younger children attended the unpublicized Coldplay benefit concert at Stephen Talkhouse in Amagansett.