Sideshow: 2 separated celebs having a ball

Breaking up doesn't have to be so very hard to do, as two celebs teach us this week.

Johnny Depp, 49, who crushed our, er, Vanessa Paradis' heart six weeks ago, made his first major public foray Monday, rocking out with Aerosmith at the band's Hollywood Bowl concert. "I need a little help up here. Johnny Depp, are you in the house," front man Steven Tyler shouted as the audience went into a mystical, whirling dervish-type frenzy.

Sporting thick eyeliner, Depp hugged guitarist Joe Perry and took up a six-string as Tyler launched into "Train Kept A-Rollin'."

No dervish-fever for Katie Holmes, but the recently emancipated Tom Cruise vassal is having a grand time. She's "blissfully happy," Anonymous Source tells RadarOnline. Katie, 33, is reportedly ecstatic to be free of Cruise's alleged dictatorial control over the projects she chooses. "Now she has full control over what she wants to do and that freedom is exciting for her," says the source.

Barbra Streisand, 70, who has retired and unretired from touring dozens of times since 2000, has chosen to launch her very last and final tour in Philadelphia. The tour, which is her first in six years (did we mention it will also be her last?), begins on Oct. 8 at the Wells Fargo Center. Info: 1-800-298-4200 or www.comcasttix.com.

All this incessant talk about losing weight, getting great abs or great glutes or great shins is unhealthy, Gwen Stefani tells Harper's Bazaar in its fattest issue in the mag's 145-year history. (It's 375 ad pages.)

"I hate talking about my body [all the time]. It's ridiculous," says the No Doubt singer, who has awesome abs. Gwen, 42, says people keep asking her about her stay-slim secret. "There is no secret," says the mother of two. "You just have to eat healthy, work out, and torture yourself."

The soul-baring interview also reveals that Gwen always has "been a girl who loves to dress up" and put on makeup. That's the way hub Gavin Rossdale wants her, she says, all dolled up. The couple are at work on the first No Doubt album since the band's 11-year hiatus.

With 1960s comedy team Stiller and Meara (Jerry Stiller and Anne Meara) as parents, Ben Stiller was bound to be a funnyman. But cutting-edge auteur? That's what he is, says the American Cinematheque, which will give the "Renaissance man of comedy" its 26th annual award at a Nov. 15 gala in Beverly Hills.

Model and cocktail waitress Megan Rossee, 25, who has overcome the odds to date Olympic swim champion Michael Phelps, is a woman of substance. HollyScoop.com says Megan turned down several offers by clothing brands to wear their wares in the stands during Phelps' competitions. Phelps himself isn't sponsor-clean: Kellogg's, Subway, Omega, Speedo, and others own pieces of his gold medal-winning legs, abs, and arms.

Would CSI star Marg Helgenberger, who dissed Justin Bieber as an intolerable brat when he guest-starred on her show, work with the Bieb again? "Of course!" she exclaims in italics to TMZ. . . . Haitian American thesp Meta Golding (Day Break) will play Katniss Everdeen (Jennifer Lawrence) foe Enobaria in The Hunger Games: Catching Fire. . . . "Going to Law School [at USC] very soon and so excited and can't wait!" tweets Kourtney, Kim, and Khloé Kardashian's lil' bro, Rob, 25. A Kardashian of his generation in school post-grad? Must be the black sheep of the family.

The School of Pennsylvania Ballet will hold its last open auditions for the 2012-13 school year on Aug. 18 at the ballet's studios at 3502 Scotts Lane, Philadelphia. Check-in for ages 8 to 12 is at 9:30 a.m.; dancers 13 to 18 need to check in at 11 a.m. Info and registration form at www.paballet.org/school-auditions.

An item Tuesday about local-warbler-Alecia Beth Moore-turned-megastar-Pink incorrectly identified her hometown. It is Doylestown. We apologize if anyone was injured due to this human, all-too-human error.