Gavin Furious As Gwen & Blake Go Public With PDA-Fest

Gwen Stefani and Gavin Rossdale's divorce is settled, but the former Bush front man is furious that his No Doubt ex has moved on so quickly with her costar on The Voice, Blake Shelton, RadarOnline.com has learned.

Rossdale is "disgusted that Gwen is acting like a lovestruck teenager," an insider told Radar. "It's unflattering for a forty-six-year old mother of three."

"Gavin believes Gwen is using the divorce to promote her new album for sales, and dating one of the biggest country music stars certainly will help boost the bottom line," the source said.

The parents of Kingston, 9, Zuma, 6, and Apollo, 1, had "hoped to keep things amicable, but they are no longer communicating," the source claimed. "Any discussion about the kids is being done through the nanny or e-mail."

In addition, Rossdale is "concerned that the kids are going to get very upset if Gwen starts spending a lot of time with Blake so quickly after the divorce," said the insider.

"There is a lot of jealousy that Gwen has moved on so quickly, and Gavin is very insecure about his career as a musician too," the source said. "Having his wife get involved with a huge star like Blake is certainly a blow to Gavin's ego."

Meanwhile, "Blake has been very attentive to Gwen, and is constantly complimenting her," the source revealed. "He thinks she is not only beautiful and very talented musically, but a great mother. The kids always come first, and Blake respects that."

Even though Gwen and Blake have always been flirty with each other while on The Voice, "Nothing happened until Gwen's marriage ended," the source insisted. "There was a very strong friendship already in place."

"Blake and Gwen have been very supportive of each other as they go through their respective divorces. Both were very public and made headlines. So now, they are just enjoying spending time together, quietly."

"Gavin was often moody, reclusive and secretive with Gwen," the source claimed. "Blake is just the opposite with Gwen. He is an open book and not complicated. It's just incredibly easy between Gwen and Blake."

"Blake and Gwen are also very supportive of each others careers, which has been another great change in her life," said the source. "Gwen felt that Gavin resented her success, and she was constantly apologizing for work commitments. With Blake, there is no apology; he gets it."