Gwen Stefani opened up on Monday, Nov. 9, about her "unexpected" split from Gavin Rossdale. Credit: Earl Gibson III/Getty Images

Picking up the pieces. Gwen Stefani shared more details about her shocking split from Gavin Rossdale, which she described as "unexpected" in a new interview with KIIS FM's JoJo Wright on Monday, Nov. 9.

Stefani, 46, and the Bush frontman, 50, announced in August that they were splitting after 13 years of marriage. According to Stefani, however, the separation began long before they formally confirmed the news in a joint statement.

"I had been writing because my life blew up," The Voice mentor told Wright. "Everybody knows that my life blew up last February. I'd just been dealing with that. Unexpected. I was going along thinking that was going to be the rest of my life and it's not. I don't know what happened."

Luckily, Stefani has moved on. The terms of her divorce were settled in August, and she's since released a smash new single, "Used to Love You" — and stepped out with her new man, Blake Shelton.

"There was one night, the epicenter of the whole thing — that's the most I can say about that — and the next day I wrote the chorus to 'Used to Love You,'" Stefani recalled. "But I didn't know it was 'Used to Love You.' I just had written all this stuff and it had happened to be in there buried in a bunch of lyrics that I had written."


Take a look back at their romance above

The songstress, who shares sons Kingston, 9, Zuma, 7, and Apollo, 20 months, with Rossdale, said the emotions she felt after her split allowed her to find her musical niche. "I've always wanted to write music so desperately because doing it is one thing that really validates me for myself," she shared. "Being able to songwrite and look back at those treasures of music is just everything to me. But there's been a lot of insecurity about it, and times where it doesn't work."

Creating lyrics in the wake of her split was cathartic, though. "I just knew that I needed to write. Even the first day that I went into the studio, I didn't want to get out of bed," she shared. "You know when you're so down that you just don't want to do anything? I went to the studio and I wrote a song. And it wasn't just writing a song to a track or something. It was like sitting at a piano with a guy I didn't know and an engineer that's sitting there who I didn't know, and all this stuff is going down they didn't know."

Stefani's latest interview echoed what she told Ryan Seacrest last week. "I think within eight weeks I had 19 songs," she told the American Idol host. "I was like, 'Listen, all I wanna do is — I just want to say the truth. I just want the truth to come out. I just want to be honest and real, that represents where I'm at right now.'"

The singer was open to discussing her life "right now" — which includes fellow Voice coach Shelton — but Wright didn't really pursue the topic further. "Ask me whatever you want and I'll decide if I want to answer it. How about that?" Stefani challenged the radio host on Monday. However, he cut to commercial.

Later that night, she and Shelton taped their first live Voice show together since confirming their romance exclusively to Us last week.

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