Kelsea Ballerini's "Legends," the lead single from her sophomore album, Unapologetically, is poised to be her fourth No. 1 hit. Written by Ballerini, Hillary Lindsey and Forest Glen Whitehead, the tune came about when Ballerini was going through a particularly dark time in her romantic life.

Now that Ballerini is happily engaged to her fiance, Morgan Evans, she no longer feels the angst of a broken heart. Thankfully, though, she has found that "Legends" is still applicable to her life, just in a different way.

Below, Ballerini shares with The Boot the story behind "Legends."

It’s a chameleon. It’s the first song that I’ve ever written that has changed meanings for me.

I wrote it from a breakup three years ago, because I had written a lot of "Get Over Yourself," "Miss Me More," "Graveyard" kind of songs -- angsty, dark, mad, sad. But I was so ready to be over it, and I think that to really be over it, you have to acknowledge the good. So that was my song of acknowledging the good, in a very bright way.

And then when it was time to pick the single, this song kept raising its hand. And I was like, "Man. This isn’t where I’m at anymore, and I don’t know if I relate to it anymore like that." So I started listening to it, and it changed meanings for me. It’s a love song to me now, and it’s about a love that you’re nostalgic about, that doesn’t necessarily have to end. So it’s the last song on the record because, to me, it’s kind of like that forever, which I think will open up to start the next chapter of whatever that looks like.

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