The former couple called time on their romance last month but were spotted hanging out backstage at Spike TV's Guys Choice Awards over the weekend.
But a source told PopEater that the 26-year-old actress likes to stay friendly with all her exes, including her estranged husband Ryan Reynolds.
"If you remember after Scarlett confirmed her split from husband Ryan the two continued to see each other and have dinner together," said the insider.
"She is incredible. Just because you are no longer with someone doesn't mean you stop caring about them and never want to see them again. She still cares a great deal about Sean and couldn't imagine seeing him at an event or award show and not saying hello. Only children act like that."
With Scarlett filming The Avengers in New Mexico and Sean having been in France to debut his films The Tree Of Life and This Must Be the Place at the Cannes Film Festival, a second source added that distance had been a contributing factor to the breakdown of their relationship.

"It's almost impossible to have a relationship when you work as hard as these two," said the insider. "Both of them are at the top of their game and getting offered role after role, which often takes them away from home for months at a time."

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