While initial reports cited struggles with conflicting schedules and travel and a fizzled-out romance, sources tell Us Weekly a nanny named Mindy Mann may have also been involved in the split.
An insider close to the family reportedly said Gwen ended things with her husband when she discovered texts between Gavin and Mindy featuring nude photos and plans to get together for sex.
"The iPad was linked to Gavin's phone," the source said. "One of the other nannies discovered the exchange and told Gwen."
When Gwen confronted Gavin, he reportedly dismissed the communication with Mindy as a "flirtation." Gwen was still "completely devastated," according to the source.
Similar allegations surfaced when Gwen and Gavin first announced their plans to divorce in August, at which time Radar claimed Gwen suspected Gavin had been intimate with the nanny in charge of caring for the couple's three children, Kingston, 9, Zuma, 7, and Apollo, 20 months.
"My life basically blew up in my face," Gwen recently said of the split. "And now I'm in this new life, and it's pretty awesome I have to say -- I'm so inspired and being back on ['The Voice'], and just being in a new place. Everything just feels new. I just feel inspired. I don't know how else to describe it."
Last week, a rep for the No Doubt singer confirmed she recently started dating her co-star, Blake Shelton.
Asked to comment on the latest infidelity rumors, Gavin's rep declined to speak on the matter and Gwen's spokesperson could not be reached. The initial Radar report was never confirmed.