On Thursday's Jersey Shore, Sammi "Sweetheart" Giancola frets over Ronnie's rumored infidelity, so she turns to Mike "The Situation" Sorrentino to get some answers.

"He's 100 percent wrong," he tells her. "You don't see that?"

Even after getting an "anonymous" note claiming Ronnie's been cheating, Sammi is uncertain.

"Come on, Sam!" The Situation tells her, adding that she looks "stupid."

Sammi shoots back, "If you saw it, you should tell me..."

The Situation implies that whatever the note said is probably true.

"I'm done," she declares. "I'm done."

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Watch a new episode of Jersey Shore Thursday at 10 pm (EST) on MTV.