Ryan Phillippe and Abbie Cornish are on

By Stone Martindale Jun 7, 2008, 0:29 GMT

10/01/2007 - Abbie Cornish - hmmm... © Glenn Harris / PR Photos

Actor Ryan Phillippe has gone public with Abbie Cornish, the actress at the epicenter of the bust-up of his marriage with actress and mother of his two children, Reese Witherspoon.

"They were adorable," a source at the Australians in Film 2008 Breakthrough Awards in Beverly Hills told People magazine. "He had his arm around her and they were cozy and comfortable."

Phillippe and Cornish were co-stars in the recent Iraq war film "Stop-Loss."  It was in Texas on the set of this film the two allegedly hooked up.

When 25-year-old Cornish who was being honored with a Breakthrough Award, was introduced, Phillippe, 33, rubbed her back while she leaned against his shoulder. Throughout the evening they held hands, People reported.

Still adjusting to his divorce with Reese, Phillippe said it's strange to see Witherspoon, 32, with her new boyfriend, actor Jake Gyllenhaal, 27 arm in arm.

"It's bizarre," the actor told USA Today, adding that he avoids looking at photos of Witherspoon with Gyllenhaal.

"I love her and I want her to be happy, and it seems like she is," Phillippe told shock jock "The Howard Stern Show," adding that Gyllenhaal is "a good dude."

"Leading up to it, we had been spending so much time apart," he said. "That's a huge part of it. There are so many obstacles."