Hilary Duff is opening up. In her interview for the April issue of Cosmo, the newly single cover girl shared some sexy new revelations.

“I’ve enjoyed myself,” she told the magazine. “I think everyone should have something where you know it’s not exactly what you’re looking for, but you just have a wicked good time. That was freeing for me and a bit of an awakening. It’s fun to have a secret.”

She played it coy when discussing Good Charlotte frontman Joel Madden, who she started dating in 2004 when she was just 15. Madden was 25 years old at the beginning of the relationship.

"I had a 26-year-old boyfriend," Duff said. "So everyone can make their own assumptions about what I was doing."

Replace any residual images you may of that fresh-faced, squeaky-clean tween who made Lizzie McGuire come to life. Hilary is clearly all grown up — and has the super hot bikini selfie to prove it.

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