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Well, it was fun while it lasted.

After three months of dating, Amanda Seyfried, 25, and Ryan Phillippe, 36, have called an end to their three-month romance.

“They are not dating anymore," a source reveals to "And it’s not a big deal for either of them.”

That seemed clear on Saturday when Phillippe hit on Rihanna, 22, at the Gucci/Roc Nation brunch at L.A.'s Soho House.

"He said something to the effect of, 'What are you doing tonight?'" a witness tells the new issue of Us Weekly.

As for his short-lived fling with Seyfried, a second insider explains, "At one point, there was a chance it would develop into something more serious, but it never did."