Mario Lopez didn't just cheat on Ali Landry. He slept with someone else days before their wedding.
Lamar Odom didn't just go on a drug binge. He went on a binge with his penis during an ugly run in 2013, while still married to Khloe Kardashian.
We can't confirm this one. But Rob Kardashian says she slept with "like 20 dudes" while dating him.
Nick Carter has admitted it: he cheated on Paris Hilton with Ashlee Simpson... a long time ago.
It's old news, but we know it's true: Brad Pitt did cheat on Jennifer Aniston with Angelina Jolie.
David Boreanaz slept with Rachel Uchitel while married. Yes, he has something in common with Tiger Woods.
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