Rob Carr / Invision/AP 1 / 6
Rob Carr / Invision/AP 1 / 6

Seems like no one wants to get hit by the fallout from Jessica Simpson's birthday-eve dumping by Tony Romo. Nick Lachey and John Mayer have both distanced themselves from the situation (the former directly, the latter through a pal), and now two other parties are doing the same.

First up is Kenny Chesney, who is shooting down a report from Star magazine that claims the starlet engaged in a "shameless flirt-fest" with him at a Fourth of July shindig, five days before the couple called it quits.

"She was giving him all her attention, and they seemed very intimate," says a spy. "They were sitting so close, their heads were together."

RELATED: See photos of Jessica Simpson

This was supposedly "the last straw" for the Dallas Cowboys quarterback, who "looked real jealous that she was talking to Kenny," according to a second source.

But the perma-cowboy-hatted country crooner, who has kept his love life low-key since his marriage to Renee Zellweger was annulled in 2005, insists that's not what happened. At all.

"Tony's a friend, and I wouldn't flirt with a buddy's girlfriend," he assures People magazine. "More importantly, Jessica was just being sweet and there was nothing else to it. It's not funny. There were no problems. Everybody got along great. After the party, everybody went their own way and nobody thought anything more about it. Period. End of story."

Oh, and one more thing. "If a girl and her boyfriend can't go to someone's house for a Fourth of July party and talk to the other guests without it turning into a big nightmare," adds Chesney, "then I feel really sorry for Jessica and Tony, who're both really nice people."

RELATED: Read about Jessica's extravagant $100K boat gift

Meanwhile, the father of the so-called "younger, skinnier blonde" branded as "the other woman" on the cover of the latest Us Weekly is coming to her defense by insisting she's not romantically involved with Romo.

The mag alleges that in the months before he ditched Simpson, the NFL-er was carrying on an "emotional affair" with one Natalie Smith, 22, sending her "flirty texts" and even introducing her to Simpson at one of her concerts back in February.

But Natalie's dad, John Smith, the associate athletic director at Romo's alma mater, Eastern Illinois University, pooh-poohs to People that the two are just longtime pals, calling the wooing whispers "very silly."

RELATED: Is Jessica Simpson a *bright* blonde?

"His breakup brought all these rumors and stories and it is not true," he scoffs. "Natalie feels so bad. Just being friends with Tony has disrupted everyone [from] talking about Tony and football and are instead talking about Tony and all of this."

As for Us' claim that Romo flew Natalie out to Dallas for a "three-day rendezvous at his home" about a week after he ditched Simpson, Papa Smith downplays that they simply had lunch.

Jessica, meanwhile, has been spending her post-Romo time scoring free jewelry and feeling the burn. This week, the already enviably shaped star has been repeatedly snapped heading to and from workout sessions with trainer Harley Pasternak.

RELATED: Who else makes our list of celebrity fitness fanatics?

And while this seems like a positive way to channel her energy in the midst of the breakup drama, OK! magazine has decided to label it her "revenge bikini diet," which she's ostensibly on because she doesn't want to "play the role of pitiful plump punchline any longer."

It's okay to groan right about now.

Anyhoo, Jess has purportedly lost 10 pounds in 10 days (again, not that she needed to) and is feeling confident that a slimmer silhouette will be good for her image.

"She doesn't want to give anyone more reason to not take her seriously," explains a pal. "She's tired of weight being a talking point."

Next: Celebrity Behavior Watch, featuring Ryan Reynolds and Katherine Heigl