Blake Shelton Shares Details on Beginning of Relationship With Gwen Stefani

06/03/2016 09:54 am EDT

While Blake Shelton and Gwen Stefani are a high-profile, crazy-in-love couple now, Shelton reveals that things weren't always this way. In a recent interview with Rolling Stone, the country star explained that the pair started things slow, first becoming friends before they began a new relationship.

"If you had told me that that's who I'm gonna end up with, I would have thought you were crazy," Shelton said of Stefani. "But she became my closest ally."

In 2015, both stars saw the demise of their marriages — Shelton's to Miranda Lambert and Stefani's to Gavin Rossdale — which led to the Voice coaches connecting on a more personal level.

"We were starting The Voice last year, and I had to sit down and go, 'Look, by the time this thing airs, my life will have completely changed, and we need to talk about this now because it may affect what we talk about on the show,' " Shelton said of his divorce from Lambert.

"I just felt like there doesn't need to be secrets," he added. "And then the same thing [happened] with Gwen."

"That's how we even found out what was going on," Shelton explained. "And we just started to develop a friendship after that. And it took awhile, because it's chaos. But just over time, seeing each other a lot at work, it just kind of developed into that."

And by "that" he means a relationship, one that is clearly still going strong — Shelton and Stefani recently performed their new duet, "Go Ahead and Break My Heart," at the Billboard Awards in May.

"We realized that we were both having a hard time letting our guard down," Shelton said of the song. "But I sent a voice memo to her, and then she sent back her verse to me. We wrote it communicating to each other. And that's why it's so special to the both of us."

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