Revenge of the ex! Lately, Gwen Stefani and Blake Shelton have seemed more in love than ever — but it looks like all that’s about to end, thanks to her ex-husband, Gavin Rossdale. In Touch has exclusively learned that the Bush rocker has taken issue with Blake’s close relationship with his three sons, 11-year-old Kingston, nine-year-old Zuma, and three-year-old Apollo.

“The kids talk about Blake all the time,” the insider tells In Touch exclusively. “So Gavin asked the boys to stop talking about Blake. Gavin told Gwen that since he only has the kids half the time, he doesn’t want to be talking about his ex-wife’s boyfriend.”

Understandably, the tensions between her ex and her new man has had an effect on Gwen and her boys. “This is taking a huge toll on her,” the insider says. “And it’s obvious Gavin is getting a thrill out of it.”

And Gavin isn’t letting his situation go to waste. According to the insider, he’s taking advantage of the vulnerable spot Gwen is in to hit her where she hurts — and give her unsolicited relationship advice that has her feeling insecure. “Gavin pointed out to Gwen that she and Blake had been spending a lot of time apart,” the insider tells In Touch. “He told Gwen she needs to focus on Blake and put her career on the back burner. He told Gwen that if he had to do it all over again, he wouldn’t have spent so much time away from his family by touring. It really moved Gwen to tears.”

If Gavin’s goal is to sabotage their relationship, it’s working. The insider says that Blake has grown increasingly frustrated that the only fights they have are about Gavin’s presence in their relationship. Despite Gavin’s ongoing interference in Gwen’s relationship, the insider says Blake knows he has nothing to worry about — and insists a wedding is even in Gwen and Blake’s future.

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