'RHONY' Star Tinsley Mortimer Is 'Totally In Shock' Following Co-Star Luann de Lesseps' Relapse
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Tinsley Mortimer was unaware that "Real Housewives of New York" costar Luann de Lesseps was struggling and says she was stunned by her decision to re-enter treatment.

Luann de Lesseps checked back into rehab earlier this week, forgoing her participation in the "Real Housewives of New York" Season 10 reunion -- and her costar, Tinsley Mortimer, is stunned.

When Andy Cohen asked Tinsley about the relapse on Wednesday's "Watch What Happens Live," she shook her head and said, "Totally in shock."

"I was so proud of her for everything," Tinsley said. "I had a mugshot in Palm Beach, too, and I just feel like I turned it around, and it felt like she was doing that. And the cabaret show is so amazing, and I was just so proud of her. It's just sad. I wish her the best, and I hope that she can work everything out."

Luann checked herself back into rehab on Monday, authorizing Bethenny Frankel to release a statement on her behalf. Bethenny told People, "This weekend, Luann was surrounded by her girlfriends and decided -- with their support -- that in light of recent circumstances, it is the healthiest choice for her not to attend Tuesday's reunion taping so that she can continue in her healing process."

"Luann is now surrounded by a core group of people who truly have her best interests at heart and who are working to make sure she gets the help she needs," she added.

"Bravo has been very supportive of Luann during this time," she continued. "It's a brave and honest decision by her, and everyone is rallying around her and wants the best for her."

Bethenny also said that "recent additional family stress was a catalyst to her taking a break," likely alluding to Lu's ex-husband and two children -- Alexandre, Victoria and Noel de Lesseps, respectively -- filing a lawsuit against her claiming she didn't keep her end of the divorce deal she signed back in 2009.

Bravo also confirmed Luann's absence from the Season 10 reunion, saying in a statement, "Bravo supports Luann's decision to focus on her health. She is part of the Bravo family and we continue to stand by her as she copes with this challenging situation. At this time, we hope everyone will respect her privacy."

Luann was arrested in Palm Beach, Florida, on December 27, 2017 and charged with five crimes, four of which are felonies: battery on a law enforcement officer, resisting arrest with violence, and two counts of corruption by threat. She allegedly told cops, "I'm going to kill you all." She pleaded not guilty and entered treatment immediately.

Luann celebrated six months of sobriety earlier this month.

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