Jason Isbell and Amanda Shires are divorcing after nearly 11 years of marriage

One of country music's premier power couples is splitting up.

Jason Isbell filed for divorce from Amanda Shires last month, after nearly 11 years of marriage, according to documents obtained by PEOPLE. The documents list Dec. 3 as their date of separation, citing irreconcilable differences.

The Grammy-winning artists share an 8-year old daughter and have been musically linked for years, with Shires playing the fiddle and singing backup for Isbell's band, the 400 Unit, and him playing guitar for her country supergroup the Highwomen.

Reps for Isbell, 45, and Shires, 41, didn't immediately respond to EW's request for comment Thursday.

Their love story dates back to 2003, when Isbell first saw Shires playing the fiddle in Billy Joe Shaver's band. They crossed paths again two years later, when Shires was with the band Thrift Store Cowboys and Isbell was in Drive-By Truckers. Shires heard he was famous and had him sign a polaroid. Afterward, Isbell pulled up a chair to watch her perform. 

"I walked in and you guys were playing and there was very few people there," Isbell recalled to Shires in a 2018 interview with Rolling Stone. "I just took a folding chair and set it down in the middle of the stage, right in front of you, and sat down and watched. Now in hindsight, that seems really creepy, I would never do that."

He added, "I was like, 'That's that girl that played with Billy Joe Shaver, it's gotta be.' Because she had the same boots on."

The two kept in touch and began to collaborate musically, starting with Shires playing on Isbell's 2011 album, Here We Rest. They became a couple soon after, and married in February 2013. They welcomed their daughter, Mercy Rose, two years later.

Since tying the knot, the two had openly discussed the challenges of their marriage, including their dual music careers and Isbell's sobriety. The 2023 documentary Jason Isbell: Running With Our Eyes Closed offered fans a closer look at those issues, showing how their professional and personal lives entwined. Along with tense scenes of the couple in the studio, the film saw Shires broach the subject of marriage counseling with her husband.

Reflecting on the doc earlier this year, Isbell told GQ, "The documentary was a pain in the ass for me. I'll never go back and watch it again. But we told people the truth, and it was good they saw that, because that's the job."

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