Kelly Clarkson's life is often an open book, but there is one thing she has never told anyone ... until now. During a recent visit to The Ellen DeGenres Show on Tuesday (Oct. 4), Clarkson is told that $10,000 will be donated to the Breast Cancer Research Foundation if she tells the host something juicy during the 'Celebrity Confessions' segment.

"Well, there's a couple that I could tell you backstage for the $10 grand for breast cancer, but I cant tell the world," Clarkson says, laughing. She does come up with something, but admits she's afraid to tell the audience because she's "a horrible human."

"This is a horrible human story but I was 18 and I had literally been on two dates in my life," Clarkson shares. She explains how a man kept asking her out while she was waitressing at a comedy club. He wouldn't take no for an answer, so she finally said yes.

"I am super self-deprecating. I applaud it. I think it's the funniest thing ever to a point," she says. "He was 5'2" and proceeded to talk about his height for a solid hour and then I went to the bathroom and then I left."

As the audience laughs and DeGeneres tries to find out how exactly she walked out of the restaurant without him noticing, Clarkson realizes how bad her story appears.

"I'm going straight to hell, I'm aware. It's the worst thing I've ever done, honestly. It was bad, y'all!" she adds before apologizing to the camera. "If you're out there, I'm so sorry. I'm a horrible human. In all fairness, I was 18. Honestly, I couldn't take it. I was working three jobs and I was tired. When you choose to go on a date with someone, I just wanted a meal and a laugh and that's it. And this is why I didn't date. It doesn't end well for them."

Clarkson was able to redeem herself, saying she never stood someone up again, even when through one more really bad date in her 20s. Her reasoning? The wine helped.

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