The pair, whose monthlong fling kicked off in April with PDA galore at the Coachella Music Festival, started their evening at local hot spot The Dove before heading to a warehouse party, where they hung out into the wee hours.
Katy, 27, who was rocking a green dress, a black leather jacket and purple tresses, tried to keep her distance from Ackroyd in front of the paparazzi (see pic below), which is quite a change from their previous public handsiness.
The soon-to-be-ex-Mrs. Russell Brand supposedly called time on the romance in mid-May because of career commitments and trust issues.
"Rob is a good guy, but she just wants to focus on her work," a source told E! News. "She's still dealing with getting over her marriage, and it's going to take her a while to truly be able to trust anyone again."
Us Weekly echoed the amicable nature of their split.
"It's not a nasty thing, and they are still talking, but Katy told him to do his thing and they'll talk soon," a source explained, with another adding, "No hard feelings. She's really busy and so is he."
Whatever the state of her relationship with the strapping Ackroyd, she still has her friends -- and her sense of humor. During a recent radio station interview, Katy was asked whether she was planning a musical collaboration with BFF Rihanna.
"No," she said. "But we're gonna have sex."
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