Kelly Rowland's been through a lot in her 30 years on this planet, but she's never really talked about her troubles—until now. The "Motivation" singer got candid in her cover story for the new issue of Cosmopolitan, discussing her failed engagement, her plastic surgery and her estrangement from her father.

Rowland revealed the reasons she called off her engagement to NFLer Roy Williams in 2005. "I was too young for marriage," she says. "I remember my sister [Beyoncé] asked me one question: She said, ‘Well, you know what you want now, don’t you?’ And I was like, ‘Yes’. It was so hard and embarrassing because everyone knew. I’d posed for the front cover of a magazine in my wedding dress and it was on sale! But sometimes you fall down and you learn from it."

She went on to say she has no regrets about her decision, and is making the most of the single life. "Before, I’d want to lean on somebody," she says. "Now I love the fact that I can just be a single lady, chilling and hanging with my friends, and traveling the world.  It’s a pretty good life. I’m ready for marriage when the right time comes now, though."

Kelly also talked about her breast enhancement, which was criticized by many who thought it ran counter to Destiny's Child's message of female empowerment. "I said in an interview a long time ago that I’d get it done because I just had little nuggets for boobs and it was bothering me," she said. "The decision was 10 years in the making, so I’m comfortable talking about it. It’s something I really wanted to do for myself—not for a man, not for work, for myself…and I love them.

Kelly even talks about her relationship with her estranged father, who she hasn't for nearly two decades. "He reached out to me saying he wanted to see me, but it’s unfortunate he did it so publicly," she says, referring to his interview with U.K. Mirror this past June. "I want to meet him, and soon, I really do. I forgave him a long time ago. I haven’t seen my dad for almost 20 years. It’s nothing I want a pity party for. He left me and my mum, and I was angry. I wanted to be a daddy’s girl so bad. God damn The Cosby Show, because that made me think, 'Why aren’t my family like that?' But this is not a perfect world."

To check out the rest of the interview, along with some gorgeous pictures of Kelly, pick up the newest issue of Cosmopolitan.

(Photo: Cosmopolitan Magazine, November 2011)