Arterton, 27, is said to have split from Catelli, 40, a few months back by mutual consent, though a spokeswoman declined to comment. Cooper tried to cheer her up by taking her to happening places in the town, reported Daily Mirror.
"Brad and Gemma have become firm friends and, as she is feeling down at the moment, he wanted to show her a good time while he is in London. Brad is a really nice guy and he and Gemma seemed like they were getting on very well," a source said.
"After hanging out at Harvey Weinstein's 'Silver Linings Playbook' bash at Little House Restaurant, they decided to share a car to Rose, where they spent a few hours partying together at a table," the source added. Arterton started dating Catelli, who works for a British fashion marketing company, in 2009, and married him a year later.