Jocelyn Wildenstein’s Longtime Partner Lloyd Klein Says ‘She Died in Her Sleep Very Peacefully’ (Exclusive)

Jocelyn Wildenstein’s longtime partner, Lloyd Klein, is sharing a few intimate memories of her final hours.

In an exclusive conversation with PEOPLE following her Tuesday, Dec. 31, death at the age of 84, which AFP and Paris Match first reported, Klein revealed that the Swiss socialite, who was known for her extensive and extreme plastic surgeries, died while taking a nap.

“We had a nice happy hour the same night and we were getting ready for the new year, and we took a little nap just to look good before getting dressed,” he says.

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When asked by PEOPLE what was Wildenstein’s cause of death, he says that the she had phlebitis, a condition that Healthline describes as inflammation of a vein that may be caused by damage to the vein wall or by a blood clot that blocks a vein.

“Because of her phlebitis, the legs were very, very swollen, and the blood was blocked, and there was no oxygen in the brain,” he says. “And we were having a nap and when I wake up, I said, ‘Jocelyn, we have to wake up, we have to get dressed,’ and she was cold and she was dead.”

“It’s very sad. It’s extremely sad,” he notes. “It’s extremely sad to lay down with your other half that I know for 21 years and waiting to celebrate New Year’s Eve and to find her cold.”

Klein says that the condition, which her grandmother also had, did not impact their holiday festivities as her health had been “perfect” just days prior.

“We were at the Ritz two days ago. We were having dinner,” explains Klein. “Before that, we had come for Fashion Week at Chanel. Everything was good, everything was good.”

Reflecting on how the two spent the holiday season, he says it was “beautiful.”

“We were at the Ritz. We were having parties. She was in great shape. She was in impeccable health,” says Klein.

The two had been spending time in Paris, during which he says she was “very happy” and “at the top of her game.” He noted that she had made a few television appearances and was “extremely beautiful.”

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“Two months ago, she attended the Chanel show. Everyone invited us to dinner. Everyone welcomed her with red carpet. Paparazzi were following us. It was the return to Paris. We were at the top of our game. Everything was at the top,” he reflects.