Back in 2015, Kelly Clarkson released the emotional track “Piece by Piece” about two important men in her life — her father, who abandoned Clarkson’s family when she was a kid, and her now ex-husband Brandon Blackstock.

“He never walks away / He never asks for money / He takes care of me / He loves me / Piece by piece, he restored my faith / That a man can be kind and a father could stay,” she sang of Blackstock in the song’s chorus.

In June 2020, however, Clarkson filed for divorce from Blackstock after seven years of marriage, and she channeled the pain of the split into her upcoming 10th studio album, Chemistry, out on Friday (June 23). She references “Piece by Piece” in her track named after iconic actor Rock Hudson.

“When I wrote ‘Piece by Piece,’ it was a very hopeful song,” the singer told The Hollywood Reporter in a new interview. “I wasn’t able to say everything at the time. A lot of that song is about what I desired and what I hoped and what I saw in someone. And it turns out I might not be singing that song again. It turns out that I maybe did marry into what I didn’t want to do in the first place. So it’s OK now.”

She continued, “It wasn’t for a couple years, but I think that’s the thing about seeing red flags and seeing things that aren’t healthy and recognizing that and not holding on to hope and potential all the time in a relationship. So just a lot of lessons learned, which is, I guess, all you can hope for, getting that it wasn’t all for naught.”

Elsewhere in the interview, Clarkson revealed that she wrote a lot of Chemistry‘s lyrics on the plane after dropping her two children off to Blackstock. “To be just frank,” she said, “there would be times I’d fly my kids to my ex and then I’d have to fly back and then wake back up hours later for work again. And I was exhausted physically, mentally, emotionally. On those flights back when I’m by myself, those were the really hard moments. And that’s when a lot of the songs were written because there’s so much that was going on and I was processing so much. Honestly, a lot of the songs were written in those moments on the way back.”