Inside Mary Tyler Moore’s 33-Year Love Story with Robert Levine, Who Stayed by Her Side in Her Final Hours

Mary Tyler Moore battled hardships from brain tumors to diabetes throughout her marriage to Dr. Robert Levine, and he stood by her side through it all.

The legendary actress died Wednesday at the age of 80. A source told PEOPLE she had been on a ventilator and had been hospitalized with pneumonia due to complications from her diabetes, and according to her longtime rep, she passed away in the company of friends and, of course, her loving husband of more than 33 years.

Moore was married twice before she met Levine, first to producer Richard Meeker and then to television executive Grant Tinker. In 1982 — two years after the death of her only child, 24-year-old son Ritchie — Moore finally met the man with whom she would spend the rest of her days.

As fate would have it, Moore’s mother Marge fell ill with severe bronchitis that year. The actress called her regular doctor, who was unavailable, and was instead connected with Dr. Levine, who was on call that day.

“After I’d seen her mom the second time, I said to Mary, ‘If there’s an emergency, just get in touch with me,’ ” Levine told PEOPLE in 1984 of the serendipitous house call. “And Mary said, ‘Does acute loneliness count?’ And I said, ‘Yes.’ ”

A few days later they made a dinner date. Soon enough, Moore and the Loyola-educated cardiologist, who was 15 years her junior and working at New York’s Mount Sinai Hospital at the time, began spending every weekend together.

“She fell really in love,” a friend of the actress told PEOPLE at the time. “It’s been a real rebirth.”

Emanuel Azenberg, the producer of Whose Life Is It Anyway? in which Moore starred on Broadway in 1980, called Levine “one of those doctors they wrote movies about 30 years ago.”

“He’s genuinely caring,” said Azenberg. “There’s no question they’re in love. They both have too much integrity to stay with the relationship if they weren’t.”

Levine regularly traveled to be by Moore’s side while she filmed various projects over the years — and he was also deeply involved in her struggle of balancing her type 1 diabetes with alcohol, which resulted in her checking into the Betty Ford Center in Rancho Mirage, California, in 1984.

“She is not what you would call an alcoholic,” Levine told PEOPLE that year. “But it was my feeling, shared by Mary’s doctors, that drinking was dangerous to her — the type of drinking that Mary does, which is basically social drinking.”

According to him, the reason she checked into the clinic was because she had been having more frequent hypoglycemic episodes — waves of weakness, blurred vision and slurred speech, caused by a low blood-sugar level — which are common to severe diabetics and could lead to coma and, in extreme cases if untreated, to death.

After filming two movies back-to-back that summer, Levine told PEOPLE Moore “had complained there were periods when she just felt lousy.”

“It was I who said, ‘Hey, maybe the drinking is affecting your diabetes,’ ” he recalled.

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The cardiologist went on to perform a two-week study of the fluctuations in his wife’s blood chemistry, collecting blood specimens throughout the day and even waking her at night. He suggested that she cut out her after-dinner brandy and all other alcohol consumption for a trial period. Her blood chart steadied somewhat. His conclusion: Alcohol was affecting her body chemistry. It was not that she was drinking more — the problem was, “the disease is progressive and becomes more difficult to treat.”

“Everyone on the street thinks of Mary as being theirs. She’s at Betty Ford because her doctor and I thought she needed a supportive environment for abstinence,” Levine said. “Her goal is to gain some strength and understanding that it’s okay to say no to alcohol.”

Moore spent every weekend visiting his wife at the clinic, and about a month after she completed her treatment, on Thanksgiving Eve in 1984, the two wed at Manhattan’s Pierre Hotel. It was Levine’s first — and only — marriage.

“You’d never know this is her third wedding,” one friend of the actress told PEOPLE at the time. “All she talks about is her dress and how excited she is.”

Moore’s longtime costar and close friend Valerie Harper was a bridesmaid, telling PEOPLE at the time Moore was “filled with joy because she and Robert are friends as well as loving each other.”

“He makes her feel cherished,” she added. “Both families are happy, too.”

The couple shared a home in upstate New York together, which they purchased in the early ’90s.

“We began by being sensible,” she told Architectural Digest in 1991. “What we were looking for was an apartment in Manhattan with a terrace. And that became an impossible quest, we were just never able to find anything that was right — the right size, the right neighborhood, and that would accept dogs. We did wind up buying a city apartment, but we also began looking at houses.”

“The first towns that realtors showed us things in were too close to the city, too suburban — because now we really wanted to be country. ‘Can we look a little farther north?’ we kept asking, ‘just a little farther north?’ ” she continued. “And here we are. There’s not even a movie house in this town — you have to go to Poughkeepsie. Or do what we do on weekends, which is either go to bed early and forget about it or rent a movie.”

Together, the couple dedicated their time and resources to the Juvenile Diabetes Research Foundation, both serving on the international board of directors.

Ultimately, Moore credited Levine with always being able to lift her spirits.

“My husband has always been very good at getting me out of myself when I get down and depressed and all of that — never seriously,” she told Entertainment Tonight in 2013. “So, I am basically a very happy person.”