Kelsea Ballerini's new album, Subject to Change, is the most personal work she's released to date, and she's not holding back in the new songs. In a new interview, Ballerini opens up about one song in particular, "Doin' My Best," which appears to hint at a spat between her and pop singer Halsey, as well as difficulties in her marriage.

The "Without Me" singer joined Ballerini for a duet on "The Other Girl," which served as the second single from Ballerini's third studio album, Kelsea, in 2020. The song appears as the fourth track on the album, and in an interview with Consequence, Ballerini opens up about a verse in "Doin' My Best" that suggests the two have had a falling out.

“I was friends with a pop star / I put ’em on Track 4 / But I wish I could take it back, would’ve never asked / If I knew we wouldn’t talk anymore,” Ballerini sings.

“There are songs on this record that I’m a little nervous for people to hear,” Ballerini admits, adding, “I’m a human, and life is messy, and there’s some things that I wanted to take ownership for."

"It’s a little embarrassing and a little cringey, but that’s my human experience," she states, but does not elaborate on exactly what happened between the two.

Ballerini is also going through a divorce from her husband of nearly five years, Morgan Evans, and the lyrics to "Doin' My Best" reference them going into therapy in 2020.

"And therapy for one turned into therapy for two / When you get married that young, you've got a lot of sh-t you've gotta get through," she sings over an upbeat-sounding track, adding, "If I said I had it all together I'd be lying / But I'll die trying / I'm doin' my best / I'm letting the rest roll off my shoulders, baby."

Subject to Change dropped on Friday (Sept. 23), and Ballerini has released "Heartfirst" as the album's lead single. She's set to embark on her 10-date Heartfirst Tour on Saturday (Sept. 24) at Radio City Music Hall. The road trek continues through Oct. 14 in Mashantucket, Ct., with stops in Denver, L.A., Atlanta and Boston along the way.

PICTURES: See Inside Kelsea Ballerini's Dazzling Nashville Farmhouse

Kelsea Ballerini is taking fans inside the dazzling modern farmhouse that she now calls home in Nashville. The singer's new residence is filled with colorful furniture and bold-print wallpaper that she calls "maximalist," but it's also set on a piece of land big enough for her dog, Dibs, to have some room to roam.

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