There's No Doubt that Gwen Stefani and Gavin Rossdale seem like a happy Hollywood couple.

But in an interview with Elle UK, as excerpted by PopSugar, Stefani admits her relationship with the Bush frontman hasn't always been picture perfect.

"I've been with Gavin for 14 years, and let's face it, that is a huge accomplishment," she says. The two first met in 1995 on tour, started dating two years later and finally married in 2002. They have two sons together-- Kingston, 4, and Zuma, 2. Rossdale also learned in 2004 of his daughter, Daisy Lowe, now 22, from his brief relationship with singer-turned-designer Pearl Lowe.

"I feel so proud (of our relationship)-- it hasn't been the easiest journey," she admits.

"I wear make-up every single day," the star says. "I like to wear make-up for Gavin and I don't feel energized until I've put it on, then I'm ready to go."

She says her famously fit body is "a daily struggle" and confides, "I work out five days a week. I can't imagine not doing it."