In October of this year Gwen Stefani and her husband Gavin Rossdale, the lead singer and rhythm guitarist of the rock band Bush, will be celebrating their 13th wedding anniversary – a milestone that many celebrity marriages do not make.

Gwen Stefani
Stefani and Rossdale have been married since 2002

Stefani realizes that she and Rossdale are lucky to be among the select few whose marriages have stood the test of time, but she is also clueless as to how the pair have pulled it off.

“We go through so much together – it's a miracle that we could stay together this long," the 45-year-old singer, who tied the knot with Rossdale in 2002 after dating for six years, recently told Cosmopolitan in their March issue.

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Stefani believes that the secret to a happy marriage is finding the correct balance between time with your partner and time for yourself. "[Gavin's] on a short tour right now, and he wrote me the sweetest note this morning," she said. "It's good to have those days when we both do our own things. I think that's what keeps relationships going, when both people can be themselves and have their own individuality. That's especially important for women – it's hard to find time for yourself."

But the No Doubt singer also notes that being the wife to a very attractive guy always helps.

"I never really saw myself landing a guy that hot," Stefani told the mag. "I don't know if I was a nerd in high school, but I definitely wasn't the super-cute cheerleader so I never saw myself getting somebody like that. But I do think he's quite handsome. It's not the most important thing about him, but it is nice … and he makes really cute babies!"

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As well as sharing 13 happy years together as a married couple, Stefani and Rossdale are also parents to Kingston James McGregor Rossdale, 8, Zuma Nesta Rock Rossdale, 6, and Apollo Bowie Flynn Rosddale, 11 months.