On Friday (Sept. 23), Kelsea Ballerini unleashed her newest album, Subject to Change, on which she seemingly addresses her friendship falling out with Halsey.

The country star appears to reference her former friendship with the "Girl Is a Gun" singer on the song "Doin' My Best."

"I was friends with a pop star / I put 'em on track four but / Wish I could take it back, I would've never asked / If I knew we wouldn't talk anymore," Ballerini sings on the track.

Listen to Kelsea Ballerini's "Doin' My Best":

The lyrics seem to reference Ballerini and Halsey's collaboration "The Other Girl," which appears as track four on Ballerini's 2020 album, Kelsea.

Speaking to Rolling Stone about airing out her “dirty laundry” with her new album, Ballerini explained:

It’s all already out there. Putting the last album out the week the world shut down and having a season of darkness after that is out there. The fact that I’m going through a divorce is out there. Having famous friends that I post about all the time and then they’re no longer in my life is out there. The fact that I fumbled on Twitter and no longer have it is out there. So why not take ownership of that?

Speaking to People in 2018, Ballerini revealed she met Halsey in Nashville when Halsey was on their Hopeless Fountain Kingdom tour.

"I had met her before, but we'd never really hung out. I'm obviously a really big fan of her music, so I went to the show with my friends and afterwards said hi, and she didn't have a show the next day, so she was like, 'Let's go hang!' And I was like, 'Yep,'" she said.

The pair became friends and eventually worked together on "The Other Girl" for Ballerini's album.

Listen to Kelsea Ballerini's "The Other Girl" ft. Halsey:

Speaking to Taste of Country, Ballerini revealed she wrote the song a month after she met Halsey and that she immediately knew she wanted Halsey to feature on the song.

"I've never had collaborations on my records before, and it wasn't for lack of trying. On [Kelsea] I was like, 'I only want collaborations if they're my friends. I don't want to go to some pop star that I don't know… I just want to do it if it makes sense to me," she shared.

In 2020, Halsey spoke to The Boot about the collaboration.

"It was really cool, because [Ballerini] and I were both in really good places in our lives and drawing from old hurt," Halsey shared. "To be clear, this [song] is a fictional event. But just us representing those two sides of women in the equation, being like, 'No, we're not gonna let misogyny turn us against each other, instead we're empowered.'"

Celebrity Friendships That Imploded

More From B100