Ryan Phillippe and Abbie Cornish
09/26/2008 at 11:20 AM EDT
and Abbie Cornish, who only recently took their relationship public
, are thriving as a couple, according to a friend.
"They're great," Rob Brown, Phillippe's pal and castmate in last spring's Stop-Loss
, told PEOPLE last week at the Hollywood premiere of The Express
. "I was with them last night. They're good people."
Phillippe, 33 and Cornish, 26, were rumored to have been dating for months but only attended their first major event as a couple in June, when he proudly accompanied her to the 2008 Australian in Film Breakthrough Awards.
Phillippe called his divorce from Reese Witherspoon
– who is now dating Jake Gyllenhaal
– "the darkest, saddest place I had ever been."
But, says Brown, the actor has recovered well and has made the best of a difficult time. "Yeah, he's alright," Brown said. "He's in good spirits and he seems happy. And I'm happy for him."
Brown – who stars with Dennis Quaid in The Express
, about college football hero Ernie Davis, the first African-American to win the Heisman Trophy – also credits Phillippe for helping prepare him for the role as Davis.
"Every time I work with someone who's more tenured than I am, I just have to sop up whatever knowledge they have, and that’s what I did with Ryan," Brown said. "In a lot of ways working on that film prepared me for this film."
2006: Inside Ryan & Reese's split!