“She is devastated,” a friend of the Real Housewives of New York City star tells PEOPLE. “She loved him. He was her family and [her 8-year-old daughter] Bryn‘s family. Bryn loved him. Dennis was Bethenny’s partner, her family, her business partner and her best friend.”
“He helped her with things — emotionally and professionally, and he was her confidante,” the friend adds. “No question that she did love this guy.”
Shields was found dead of a suspected overdose in his Trump Tower apartment on Friday. He was 51.
On Monday, Frankel posted an Instagram of Shields cuddling with her beloved dog Cookie, who died in October at the age of 17.
“Rest In Peace my sweet babies who gave me endless unconditional love. #nowandforever,” she captioned the intimate photo.
Frankel, 47, first met the New York City-based banker almost 30 years ago when he dated (and later married) one of her high school friends, Jill. Though she didn’t stay in touch with her classmate, Frankel and Shields shared other mutual pals and began dating in 2016, several months after he separated from his wife.
Jill addressed Shields’ death in an exclusive statement to PEOPLE on Friday.
“We are all heartbroken,” she said. “Dennis was, and will always be, the love of my life. His spirit lives on in our children. Please respect our family’s privacy at this time.”
Last week, a source told PEOPLE that Frankel and Shields’ coupling was “unconventional and not always exclusive.”
“Bethenny loved him a great deal, but it was an unusual relationship,” said the source. “They would be together and then not. Sometimes these traditional relationships aren’t the best thing for everybody.”
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The source added that Shields was a “steadying rock” for Frankel.
“He was very mild-mannered and she is like a force of nature,” the source said. “But she needed that in him.”
The Bravo star was photographed looking emotional at Shields’ funeral on Long Island, New York, on Monday.