"We're singing this song like we're gonna break up and we're not breaking up right now, you know, this just seems kinda weird,' " Blake Shelton told Ellen DeGeneres
Credit: Michael Rozman/Warner Bros.

Things between Blake Shelton and Gwen Stefani are so good, the pair couldn’t help but giggle while performing their breakup anthem duet “Go Ahead and Break My Heart.”

“We kinda did laugh a few times. There was moments where it was like, ‘We’re singing this song like we’re gonna break up and we’re not breaking up right now, you know, this just seems kinda weird,’ ” Shelton told Ellen DeGeneres on her show Monday, of singing with Stefani during Sunday’s 2016 Billboard Music Awards.

During the show, Stefani and Shelton, who have been dating since last fall, faced each other, keeping their eyes locked as the crowd looked on. The tune includes lyrics like “You can’t tell me that we’ll still be friends/And maybe some day we can try again/If you really need a brand new start/Why don’t you go ahead and break my heart.”

“When we wrote the song, we never saw it going there,” Shelton told DeGeneres of singing at the BBMAs. “I don’t know that we ever really saw it going anywhere. I only started the song to impress her, to be like, ‘Hey, I’m writing a song about you.’ And so I sent it to her and she wrote the other half of the song, and it’s like ‘Oh, she just one-upped me.’ ”

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Shelton’s new album is deeply personal, encompassing a year in which he divorced wife Miranda Lambert and got together with Stefani.

“Everytime you make a record, you make a record and you have two or three things on there,” the star explained to DeGeneres.

“This is just full of all kinds of ups and downs, and the last year of my life it’s been nuts, it’s been crazy. So I just thought, you know, if all the magazines are gonna cash in on me I might as well too.”