Saying on Instagram the move was "one of the saddest days of my life," Lee moved on Monday, Dec. 14, after selling the large New Castle home known as "Lily Pond" for $1.85 million earlier this year.
The couple separated last year after a 14-year relationship. Lee has since moved to Malibu, California.
On Monday, Lee, 54, was spotted moving furniture out of the four-bedroom Colonial style home, and photos were published by Daily Mail.
The former de facto First Lady of New York said on Instagram that her last moments were "bittersweet" and that she "cried and cried"
"My last moments on Lily Pond were very BitterSweet," she posted. "I walked around the outside of my beautiful home —I wanted to drink in every angle and remember the beautiful moments that were spent in every place."
She also said she hoped the new owners would be kind and love the home as much as she did.
Lee said as she took a last look at the home, she realized a front light was left on, but when she went to open the door to turn it off, she realized it was locked.
"It was as if the house said, 'It's time to move forward Sandy!!' It was a most amazing experience and I absolutely know that House and all of its 3 beautiful acres loved us too!"
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