The 47-year-old American singer admitted in the December issue of Glamour that she worried fans would think she's a "failure" because of her split from the 51-year-old English rocker.
"I don't think you'll talk to one person who didn't make it in a marriage who's not gonna feel that way," Stefani told the magazine.
"The intention of being married is the vow, right? You want to put everything into it to make it a success."
"I had to work really hard at marriage, all the time, like everybody, but ours was extra hard, when you add that we're from different countries, both of us being in music, and celebrity. [Marriage] was the one thing I didn't want to fail at," she revealed.
"People can say whatever they want to about me... and I don't get too affected. But I didn't want them to think I was a failure. There's nothing weird about how I felt," the star said.
Stefani and Rossdale, who share sons Kingston, Apollo and Zuma, split in August 2015 after nearly 13 years of marriage.
The singer has since found happiness with country star and fellow "The Voice" coach Blake Shelton, whom she went public with in November 2015.
"[This year has been] mind-blowing," she admitted.
"I don't understand my journey. It's so crazy. But one thing I learned is, that's what life is. We all have to go through hard times. Tragedies. Those are given to us to see what we're going to do with them."
"I'm in a different place now, [and] that is the past for me. I'm in such a new place. It's all about the future for me. Not really just the future -- but the moment right now," the star added.
Rossdale himself told The Sunday Times in October that's he's ready to "move on" from his split from Stefani.
The Bush frontman said he's had "enough" of attention to his divorce and that he's focused on his children.
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