Gwen Stefani and Gavin Rossdale are very concerned about their children in light of reports the Bush rocker had cheated on her with their kids' nanny Mindy Mann for over three years.

"It's really tough for them," a source close to Rossdale told People of his three sons with The Voice coach -- Kingston, 9, Zuma, 7, and Apollo, 20 months.

"Every day there's a different story. He is concerned about the kids and wants to keep them safe and is trying to keep all this craziness out of their lives and keep things as normal as possible for them. He's just all about being the best father he can be for them."

When Stefani, 46, discovered her husband's alleged affair this past winter, she tried to shelter her children.

"Gwen didn't want the news about the nanny to get out for the sake of her kids," an insider told E! News. "She really wanted to protect them and not have them go through knowing this went on with their father and someone that she trusted."

A "completely devastated" Stefani then filed for divorce from Rossdale, 50, in August after 13 years of marriage citing irreconcilable differences. The couple said in a statement at the time they were committed to jointly raising their kids in a "happy and healthy environment."

But now that Stefani is dating her The Voice co-star Blake Shelton, she's been less guarded about the events that led to her heart break.

"Over the last few weeks, she had begun telling more of her friends what had happened. She is ready to move on and start the next chapter of her life," the insider added.

"Gwen is feeling the best she has felt in a long time despite all of [the] nanny stories circling," another source said.

Stefani had reportedly hoped the early 2014 birth of their third child would fix their marriage problems, but the exact opposite apparently happened.

The No Doubt songstress was "thinking maybe another kid would draw them close, but really [it] just brought them further apart," a third insider told E! News. "Gwen wanted to try and make it work, but in her heart she knew that she could not get past the betrayal."

Stefani fired Mann from her job, but Rossdale is allegedly still in contact with her, checking to see if she's okay with all these rumors circulating.