Yolanda Hadid and David Foster learned the hard way that staying together "in sickness and in health" is easier said than done. In a new interview for the Tuesday, March 1, episode of The Dr. Oz Show, the Real Housewives of Beverly Hills star opened up about the end of her marriage, explaining that she's no longer the woman Foster fell in love with before her Lyme disease diagnosis.

"The patient suffers, but the caretakers suffer too. Because life doesn't only change for us, it changes for the person next to you," Hadid, 52, told Dr. Oz.

"At the end of the day, David never changed, I changed," she continued. "Unfortunately, these are the cards that life dealt me. It wasn't by choice. But I'm not the woman I used to be and I probably will never be again. My focus, my energy goes to trying to get well, trying to make a difference, trying to find a cure for my children … and David's life is really traveling, going to concerts, loud music. And I mean, I couldn't, I can barely listen to the radio."

Hadid was diagnosed back in 2012, not long after she married Foster. Her kids Bella and Anwar were diagnosed the same year. (Her eldest daughter, Gigi, does not have Lyme disease.)

"It strikes the deepest chord of hopelessness inside of you," she told Dr. Oz of finding out that two of her children had the condition. "Because as a mommy, we're fixers. We want to solve [our kids'] problems and give them a fair chance at a happy life. And at this moment, my hands are tied behind my back because I don't have the answers. It's heartbreaking. Because life is tough enough."

Indeed, it was so tough at times that Hadid didn't want to go on. "My children [are] what kept me alive. I remember just waiting for them to get out of school, just to give them a hug and look at them for hope," she revealed. "They're the ones that kept me fighting and wanting to live. There were many days that I really didn't want to live anymore. But when you look at your children, it's not a choice anymore. You have to get through, you have to keep fighting and searching to get well."

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