AceShowbiz -

It is apparently only a short-lived romance for Amanda Seyfried and Ryan Phillippe. The couple, who was first said hooking up after meeting at a Halloween party, has reportedly split after dating for only three months. "They are not dating anymore," a source says. "And it's not a big deal for either of them."

During their brief fling, there was a speculation that Amanda and Ryan's relationship was getting serious as the "Chloe" actress reportedly met with her then-boyfriend's kids more than once. On this, another insider explains to Us Magazine, "At one point, there was a chance it would develop into something more serious, but it never did."

Rumor has it, the ex-husband of Reese Witherspoon has tried to hit on another girl after he split from Amanda, and his target was Rihanna. An eyewitness says, when they met at the Gucci/Roc Nation brunch at L.A.'s Soho House on Saturday, February 12, "He said something to the effect of, 'What are you doing tonight?' " Bad luck for the actor, the singer reportedly rebuffed him.

But Amanda has denied that Ryan flirted with the Bajan beauty. The blonde who will soon be seen in "Red Riding Hood" was recently caught by photographers when she was moving in to her new Hollywood pad and when asked by X17 Online about her former flame, she said, "Oh, he's a nice guy - we're friends. And that Rihanna story is not true. That is so f**king not true!"