David Foster is standing by his ex, Yolanda Foster, when it comes to her battle with Lyme disease.

The 66-year-old GRAMMY award-winning musician set the record straight on Tuesday, in response to claims that Yolanda has been exaggerating her illness.

"Over the past few weeks, a great deal of inaccurate or baseless information has been reported claiming to represent my thoughts and feelings," David said in a statement to ET. "It is painful to watch this happen repeatedly -- especially while trying to cope with the personal nature of the challenges surrounding the breakup of our loving marriage."

"I have always had and continue to have the utmost respect and love for Yolanda, which is why it is so frustrating to see headlines questioning her chronic debilitating illness," he added. "I have been by Yolanda's side over the past four years to the best of my ability as she battled with the complexities of her Lyme diagnosis. I am incredibly proud of Yolanda's determination and mission to find a cure, and how brave and open she has been by sharing her story in the hopes of changing the future for others."

WATCH: Brandi Glanville 'Livid' Over Skepticism of Yolanda Foster's Lyme Disease

Yolanda, 51, has been defending herself against claims by her fellow Real Housewives of Beverly Hills cast mates -- most recently, Taylor Armstrong -- that she's been exaggerating her illness.

"It seems like a misdiagnosis," Armstrong said at one point during a recent episode of the Bravo hit.

"What defines suffering? You will never hear someone who's walked in my shoes speak the way Taylor spoke on tonight's episode," Yolanda fired back on her blog last week. "I truly hope she never has to experience the journey she questions me for sharing."

"What I saw on the show tonight was just that: IGNORANCE," she also wrote. "Maybe it should anger me, but instead it makes me want to fight harder and speak louder for those whose voices can't be heard."

WATCH: Yolanda Foster Speaks Out About Divorce From David Foster -- 'Don't Judge Our Journey'

Earlier this month, Yolanda admitted that, aside from the obvious physical effects that her illness has had on her body, it also "changed the dynamic" of her marriage to David.

"Unfortunately, it was not strong enough to withstand the circumstances that came our way," Yolanda told host Andy Cohen on Bravo's Watch What Happens Live. "Chronic long-term illness is extremely challenging, not only for the person that's sick, but also for the caregiver. It for sure changed the dynamic of our relationship."

Yolanda and David announced they were splitting on Dec. 1 after four years of marriage.

A source close to Yolanda told ET earlier this month that the couple ultimately decided to divorce because "David is a very busy man, and always put work No. 1."

"He travels a lot for work and really did not scale back when Yolanda got ill," the source said. "She's also been sick for their entire marriage. She was diagnosed [with Lyme disease] right after their wedding, so that really took a toll on their relationship."

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