Jason Isbell and Amanda Shires are husband and wife, parents and musical collaborators: She is a member of his band, the 400 Unit, while he sometimes plays with her during solo shows and works with her band the Highwomen. The two are open about how they've maintained healthy, equal partnerships, both creatively and personally, but in a new interview with the New York Times, the couple admits that the making of Isbell's new album, Reunions, tested their marriage.

"For some reason, I felt really pressured," reflects Isbell, whose three most recent albums -- 2013's Southeastern, 2015's Something More Than Free and 2017's The Nashville Sound -- have earned him ever-increasing fame and popularity, not to mention acclaim as a talented songwriter and a generally well-liked and -respected person.

Isbell is a frequent winner, and even more frequent nominee, at the American Honors & Awards; earned both his first CMA Awards nod and the title of Country Music Hall of Fame and Museum artist-in-residence in 2017; and has four Grammy Awards to his name. He and Shires are an admired musical power couple, and he's also known as a funny and observant Twitter user.

"You think, ‘If I make a record that’s not great, everybody’s going to dismiss me entirely. If I [expletive] up my relationship, everybody’s going to be so shocked that they’ll write me off completely,'" Isbell reflects. "All those things, when you say them out loud sound ridiculous, but they stay in there and gnaw at you."

That gnawing feeling left Isbell feeling "resistant to input," he says, and "curt and on-guard" toward Shires, she notes. Shires remembers her husband being "upset, angry and grumpy" from the get-go when he began playing her the songs on his new album.

“He was impossible. It was like he wanted help but didn’t want help," Shires says, and when the two, along the rest of the 400 Unit and producer Dave Cobb, went into RCA Studio A to make Reunions, the unrest bubbled over.

"I want him to make the best art he can but not at the expense of making me feel less," Shires says, so she moved into a Nashville hotel for 10 days. "I needed space because lines were getting crossed," she explains, but adds that she "had faith that eventually he’d come to the realization that as good of a father and a person as he is ... you can still inflict harm onto people."

Isbell confesses that it "took a couple months until I wrapped my head all the way around it." He adds, "At one point, I said, ‘It’d be easier if somebody had cheated.' Then we could say, ‘You did this,’ or, ‘I did this,' and, ‘Somebody needs to be real sorry.’ But it was more like, ‘We don’t know each other right now. We’re not able to speak the same language.'"

Despite the tension and the fact that it was "the worst recording experience I've ever been a part of," Shires describes Reunions as her favorite of Isbell's albums. He, meanwhile, isn't sure if their struggles affected the final product, but says he's "try[ing] not to ask that question because I don’t want to get in a pattern of [expletive] my life up to make better records."

"I’d like to say we’re stronger because of it, but we’re not. We just know that our strength is more than we thought," says Shires. Adds Isbell, "My wife wants me to do my best work. My job is to figure out how to do that and still be the best person I can be. Anything less is not what she wants."

Reunions is due out on Friday (May 15).

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