Leah claims that she's 'in no way proud of [her] mistakes' and 'regrets' what she did to Corey.

Teen Mom 2 star Leah Messer, 19, has continually denied that she cheated on her ex-husband Corey Simms, 21, while they were briefly married for six months. But in an astonishing online confession, Leah finally comes clean about the truth and reveals that she did cheat on Corey … a week before she became his wife.

"Okay, I cheated a week before my wedding people," Leah tweeted on Feb. 1. "I'm tired of hearing about it. At least I'm not a coward, and can admit my faults!"

Leah knows that she made a bad decision. "It was one of my regrets in my life, stop accusing and pointing fingers," she wrote. "Things happen to different people different ways. GodsMyJUDGE"

"I can not not change whats happened!" she continued. "I can only be proud of where I stand now, and learn from it. I'm in no way proud of my mistakes, but last I checked we aren't proud of our mistakes."

Leah and Corey's divorce was finalized in June 2011. A month later, Leah met her new fiance Jeremy Calvert.

Hopefully, Leah means it when she says that she learned from her mistakes.

- Lindsey DiMattina

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