While Stefani may not have known intellectually what was going on, her intuition was definitely feeling something — and the stress resulted in a series of strange symptoms that left her sick and exhausted all the time.
During the time Rossdale was reportedly sleeping with the couple's nanny, Stefani "had non-specific symptoms including stomach aches, muscle pain, constant headaches and other digestive issues," an insider told Radar Online.
Doctors were unable to diagnose her with any sort of physical illness.
So Stefani took matters into her own hands. "Gwen had always been a fan of alternative medicine, and decided to try acupuncture," the source said. "She began to step it up to daily trips as her marriage was on the rocks."
And while those treatments "did give Gwen some relief, she never got complete relief from the pain," said the source.
The insider believes the stress of the couple's failing marriage, along with Stefani's suspicions that Rossdale was having an affair, made her even sicker.
"Gwen had suspected for months that Gavin had been cheating on her with the nanny, Mindy Mann. Gwen would confront Gavin and he would reply she was crazy," the source claimed, "which only made Gwen feel worse.
"There were days Gwen could hardly get out of bed. The pain was just all over. She thought she was going crazy."
Finally, her suspicions were confirmed. The day after the 2015 Grammy Awards, the couple's other nanny gave Stefani the damning evidence: texts from the family iPad including sexual exchanges and nude photos of Mann.
"Gwen was told by her staff that they believed Gavin had been cheating on her with the nanny. Gavin continued to deny it, but she knew she wasn't wrong this time.
"Even though Gwen was so angry and betrayed by the affair, she immediately began to feel better," the source said. "The vague all-over body pain was gone. She realized the marriage was making her sick."
Add this to the litany of reasons why Stefani and Rossdale will never, ever, ever get back together. She "could never forgive Gavin for letting her suffer in that way," said the source. "Her health was impacted, and he did nothing."
Now that she has dumped the toxic influence on her life, "she is sleeping through the night, and there is no more pain," said the source. "A weight has been lifted off of her."
Stefani seems to have recovered nicely — she is on top of the world with new music, her gig on The Voice and a new romance with her co-star Blake Shelton.
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