Paris Hilton spent her first night as as single girl partying in Hollywood with her sister Nicky.

Just hours after the socialite’s rep revealed she’d split from her boyfriend of six months, Doug Reinhardt, we ran into the Hilton sisters leaving the My House nightclub.

According to online reports, Paris wielded the axe when she spotted her beau eyeing up other girls while they were out together on Tuesday.

But we’re not convinced the whole thing isn’t just a publicity stunt.

The split came just days after Paris raved about the former baseball player in a series of TV interviews and internet postings.

And she didn’t look too broken-hearted when we spotted her just minutes later, engaging in a late-night texting session.

Picture after the jump

Simon Cowell left the Britain’s Got Talent studios on Friday in the company of a mystery lady after the last semi-final show.  It was just days after a crazed fan is said to have hurled herself at Cowell when he rolled his car window down upon departure earlier this week, but that didn’t stop him from rolling his window down again here and letting our photogs get a good look at his pretty companion…or at Cowell, looking like the cat who ate the canary.  As it were.

Former Danity-Kaner D. Woods and Mya, whose next album is set to drop this summer, smiled it up at the Junior Smile Couture Event 2009 to benefit Operation Smile on Wednesday night.  We like D. Woods’s kit much better than the outfit she had on for last night’s Making the Band 4 finale, in which the big DK reunion was teased and then, as usual, absolutely nothing about the disintegration of the group was explained.  Woods’s unflattering green leggings weren’t explained either.

Woods did mention that she’s working on a solo project, so look for that in late ‘09.

Marg Helgenberger makes a minor adjustment at the party for CSI’s 200th episode on Monday.  Helgenberger reportedly split from husband Alan Rosenberg after nearly 20 years of marriage, but she’s got what looks like a pretty big diamond on her left ring finger in this shot.

Good week for the Osmond family’s profile: it turns out Donny isn’t going on this season of Dancing With The Stars after all — though he says he’d definitely consider an offer for a future season.  Donny’s nephew David, who’s eldest Osmond Alan’s son, has made it through to the Hollywood round on American Idol, and hopes to go all the way in spite of suffering from multiple sclerosis.  And Donny’s little sister Marie has an “entertainment and lifestyle” talk show set to debut this fall.

Today’s “news of the weird” tidbit: the Killers’ Brandon Flowers saves his beard trimmings to give to Neil Tennant.  Oh, who doesn’t?  …Okay, seriously: why does Flowers do this?  He’s annoyed by comments the Pet Shop Boys frontman made about the beard.  Says Flowers, “He said that I only grew a beard to prove that I was more than pop. … Every time I shave, I put the hair in a bag. I’m waiting for the opportune time to give it to him.”  We think Flowers is probably taking the piss, but: okay, then.

In Touch magazine claims that Jennifer Aniston and John Mayer have split again amid rumors he’s seeing a mystery blonde on the side.  A source tells the mag that Mayer went on a date with the blonde on Wednesday night, and it’s not the first time, either: “They were obviously on a date. He came in with her another time too and I’ve seen them out together. He gave her a long kiss before they left. John has been here six times in the last two weeks but never with Jen.”

Madonna has won the right — for now — to keep her sons with Guy Ritchie, Rocco Ritchie and David Banda, with her in the States.  A source says the custody agreement between Guy and Madge is progressing “amicably,” with the boys set to divide their time between their parents on two different continents, but Madonna has temporary custody of the kids and the right to have them with her in the U.S.  Another more permanent ruling is set for mid-February.

Danity Kane’s Dawn Richard says Sean “Diddy” Combs is “devastated” over the group’s split.  The group confirmed that it’s defunct on Thursday; while Richards and bandmate Aundrea Fimbres will try to soldier on for the next season of Making the Band, which bows in February, the other three DKers — D. Woods, Aubrey O’Day, and Shannon Bex — have departed the group for good, and Combs is said to be “angry” and hurt by the fracture.  Richard explains, “He’s just confused. I think that’s what makes him crazy the most. He’s like, ‘I’m the master of all of this, and they totally pulled the wool.’ I think he’s bitter and angry.”  She denies that the dissolution was prompted by Combs grooming her for a solo career.