She says her life started to crumble "the day after the GRAMMYs," which would have been months before their divorce was made public.
Stefani and Rossdale announced their "mutual decision" to go their separate ways back in August after 13 years of marriage. The No Doubt singer's divorce petition cited "irreconcilable differences," but it is still unclear as to what was the inciting incident for the breakup.
"I feel like I don't have anything to hide," Stefani said, implying that her upcoming album is laced with clues. "What I will tell you is that I was married for a long time and now I'm not. It was like a shock."
While the first single off the album, "Used to Love You," is remarkably honest, Stefani told Seacrest that there were even more revealing tracks that she "definitely wouldn't put out, because they were too angry."
In fact, Stefani says the record company told her that some of the songs were too personal for fans to relate. Stefani said receiving that message was like a punch to the stomach, but the next day she wrote "Used to Love You."
The lyric to the chorus of the emotional single had been written prior on the day after a "major event happened."
During a previous interview with Apple Radio Beats 1 DJ Zane Lowe on Monday, Stefani revealed that her marriage made her feel like "she had been living in a cocoon, ready to bust out."
The singer explained that she had writer's block and initially surrendered to the idea of curating an entire LP with songs written by other people until she was struck with a rush of creativity after the split.
"I think I have enough probably for two albums," she said. "I got 20 songs. I want to keep writing."
Following her divorce, there have been whispers that Stefani and Blake Shelton, also recently divorced, are an item. While she didn't confirm or deny the rumors to Seacrest, she did little to squash them.
"I'm not going to answer that right now," Stefani said. "But I think he's hot, don't you?"