AceShowbiz -

Is there trouble in paradise in Gwen Stefani's relationship with Blake Shelton? Sources tell Life & Style that the "Hollaback Girl" hitmaker's "faltering relationship" with the 40-year-old country musician is weighing in on her, but she's "in denial."

"She wants the world to think everything is perfect with Blake," says an insider. "But that's just not the case anymore." The insider continues, "It's only a matter of time before Gwen and Blake announce a split. At this point, they're just going through the motions."

The webloid further notes that the couple had been trying to have a baby, but when she failed to get pregnant, "Gwen and Blake began to argue more." The source adds, "Then she started to realize they're just too different to spend the rest of their lives together."

Gwen's ex-husband Gavin Rossdale is dragged in the middle of the couple's alleged troubled relationship as he fears the split will affect their three sons, Kingston, Zuma and Apollo. The 51-year-old Bush frontman allegedly even offers to take the boys with him to allow Gwen to focus on her relationship with Blake.

"Gavin worries that another breakup will cause a lot of emotional despair," explains the source. "So he wants to sit down with Gwen and Blake to discuss everything." Gavin knows they will always be bonded by their children. "I still think she's incredible," he once said of Gwen. "I'm grateful for her every day."