Jen Aniston and Justin Theroux? Not happening. Who says so? The mother of Justin’s gorgeous long-time girlfriend, stylist Heidi Bivens!

Speaking exclusively to our friends at Star, Marilyn Bivens said Theroux, 39, and Aniston, 42, are just FRIENDS.

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“It’s not true at all,” Bivens said.

From Justin Bieber and Selena Gomez to Chelsea Handler and 50 Cent, Hollywood is rife with celebrity couples claiming to be 'just friends.'

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But as Sandra Bullock and Ryan Reynolds become the latest pair to hit the rumor mill, RadarOnline.com digs deeper into the A-list platonic phenomenon.

While many romances begin as friendships, it has become habit for celebrities and their reps to issue a statement denying they are anything more than pals.

Nothing is sexier than two gorgeous Hollywood stars in love, and RadarOnline.com has the list of the hottest hookups in 2010!

PHOTOS: Top 25 Hottest Celebrity Hookups Of 2010

Sexy star Megan Fox wed her long time boyfriend Brian Austin Green in a private beach ceremony in Hawaii on June 24.

The sultry 24-year-old started dating Green when she was only 18 and even though there were rumors of a breakup the couple says they've always been together.

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While Bristol Palin shimmies on Dancing With The Stars, her ex Levi Johnston is making his own mark on Hollywood. RadarOnline.com has the exclusive first look of Johnston’s music video with his new lady love Brittani Senser.

PHOTOS: Levi Johnston & Brittani Senser Have A Love Connection In L.A.

The video is sure to be drama-filled. The exclusive poster obtained by RadarOnline.com shows the couple locked in romantic embraces. Levi even has a run-in with the law!

The video is for Senser's R&B-pop music tune After Love and the art imitating life concept for the shoot is about a young couple's romance being thwarted by the girl's disapproving mother. (In real life, Sarah Palin voiced her wariness about Levi and her daughter Bristol's short-lived renewed plans to wed.)

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It seems Levi and Brittani’s on-screen romance spilled over to real life. As RadarOnline.com previously reported, the couple is now dating. Senser gushed that the Alaskan hunk is “bright, sensitive and funny.”

PHOTOS: Levi Johnston Takes It All Off For Playgirl

"When we worked together on making the video, I was really happy about it because I felt that Levi could understand the story and bring truth to the role," Senser told RadarOnline.com. Brittany even joined Levi in a shopping jaunt to scope out goodies for Tripp, his son with Bristol. "Working together I got to know him to be a really great guy. It was like we knew each other even though we had just met."

Kirk DeWindt has rebounded from his heartbreaking departure from The Bachelorette. RadarOnline.com has exclusive details about his recent weekend getaway with Ali Fedotowsky’s former rival Jessie Sulidis!

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Jessie and Ali vied for Jake Pavelka’s affections on the last season of ABC’s The Bachelor and Ali recently eliminated Kirk from the competition for her heart after he made it to the final four on The Bachelorette.

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Last week Jessie and Kirk met up in Windsor, Ontario. “They definitely had a romantic weekend away and I think they will be linking up again sooner rather than later,” a source told RadarOnline.com.

During dinner at a sushi bar “fans approached them all night and took pictures,” a source said. “They couldn't walk the streets or eat alone as women kept approaching them.”

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The budding new couple also went golfing.

“Kirk wanted to impress them both! He taught her a tip or two and was impressed she was a natural athlete,” the source added. “They then ventured off to have dinner at The Keg where Justin Rego randomly showed up as he was in town for an event.”

After a quick hello to “Rated R” Justin, Kirk happily turned his attention back to Jessie.

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“There was a real-life bachelorette party at the Keg and a bunch of the women came over to their booth with cake,” the source added.

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“Kirk and Jessie were so welcoming- they let the women sit with them for a bit and ate cake and took pics."

Britney Spears' former agent-turned-boyfriend Jason Trawick has spent lots of quality time with her family. Now, the pop star has returned the favor.

PHOTOS: Britney Spends Weekend With Potential In-Laws

Britney and Jason have been enjoying a getaway in Santa Barbara, California, and got some interesting company on Saturday.

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The couple stopped by Michael's Arts and Crafts store accompanied by his parents. Britney grinned widely as the group left the store with their bags of goodies in hand.

PHOTOS: Britney's Sexy Shoot