The real-life couple duets on Shelton's upcoming song, "Nobody But You," which discusses how life is bettered through a loving relationship. While speaking with ET's Cassie DiLaura backstage atThe Voiceon Monday, Shelton sweetly reflected on his romance with Stefani.
"I don't want to remember what I was like before Gwen, actually," he said.
"I'm a little bit of jerk to you still," he added, speaking to his fellow Voice coach, Kelly Clarkson. "But I was a jerk to everybody... Look how nice I am now!"
Stefani couldn't help but get emotional thinking about how her life had been affected by Shelton.
"Blake saved my life, everybody knows that," she told ET. "Like, we're just having the time of our lives, and we never expected that this late in our lives, so we're just trying to savor every moment together, and just to be back on The Voice as well -- not to change the subject -- but working together again has been really fun, and I love being here and I love being with him."
"I love the energy with them being on the show together," John Legend chimed in. "It kind of softens Blake a little bit."
This week's episodes of The Voice are big ones. The semifinals will see the cast of contestants cut in half.
"It's a lot of people to go, and there's no even mediocre singers now. They're all really good," Legend said.
"Even last week, people were going home that shouldn't," Stefani noted. "It's been really inspiring."
The Voice airs Mondays and Tuesdays on NBC. "Nobody But You," will be included on Shelton's new album, Fully Loaded: God's Country, out Dec. 13.