“Everybody thought it was a publicity stunt,” the puckish real estate mogul and Shark Tank producer/co-star says today. “I just did it to shock the shit out of my friends. And they were shocked. If they had one moment of thinking I was dead it was worth it.”

That’s why, for her 75th birthday this past spring, Corcoran, whose reported net worth is $100 million, tried something a little more staid: She spent a few days in the Cayman Islands with a group of friends—who all showed up dressed as her for a surprise—and left it at that. “I couldn’t think of a better idea [than the funeral],” she admits. “I mean, that was competing against myself! And nothing sounded like as much fun.”

Still, don’t mistake her good sense of humor to mean she’s at peace with getting older. She’s admittedly vain—and though she uses her media career to justify the three facelifts she’s had (“Every 10 years!”) and easily shares about, she believes she would’ve had them anyway.

“A lot of my self-image is what I see in the mirror,” she tells Fortune. “So if I’m looking fresh and happy, I feel good about myself the whole day.”

She also has a more serious preoccupation: that of developing Alzheimer’s disease.

“A couple of months ago, I found my phone in the freezer,” she admits. She was scared—and while a series of cognitive tests with her physician confirmed she does not have the disease, her fear of it is understandable, considering it has affected two of her good friends, her grandmother, and her mother, Florence, who died of Alzheimer’s 12 years ago at the age of 88.

Corcoran is just now coming out of a deep sadness around the experience of watching her mom disappear—a nine-year process that was very tough for about half of that time—and she’s eager to talk about it in case it could help others.

“I think it took a long time to process it,” she says.

Dealing with her mother’s Alzheimer’s

Her mom’s disease, she recalls, started with little things: forgetfulness, losing her glasses. But then she couldn’t remember her best friend’s name.

When she really “got alarmed,” she recalls, is when her mother woke up in her younger brother’s apartment after spending the night and “she didn’t know where she was.”

That’s when Corcoran and her siblings—all 10 of them, raised by their parents in a two-bedroom house in New Jersey—came together to form a care team. Her brother T, she says, led the way by signing up to take a course on how to care for people with Alzheimer’s.

“He taught all of us how to care for her and we all got on the same page,” she says. “He taught all of us to live in mom’s reality.” So when she would scream about there being a snake under her bed, for example, rather than saying, “No there’s not,” someone would go into the room, find the snake and “beat the hell out of it.” The siblings would react similarly when their mother asked for their father, who had died a few years before her illness.

“We spent time saying, ‘Oh, sorry mom, dad has passed away,’ and she’d go through all the mourning for him again,” Corcoran says. “Then T called us one day and he said, ‘Dad’s out warming up the car.’ So we all started saying to her, ‘Dad’s out warming up the car.’” For a time, her mother even carried around a baby doll, finding happiness in her regression. They went along with it.

But watching her fade away, Corcoran recalls, was “just very sad, more than anything else. Because she, as a mom to us, was a love bug.”

Relying on family support

Finding reinforcement in each other was crucial. While many siblings wind up fighting or dealing with resentments because some do more than others while caring for an elderly parent, Corcoran says they were pretty fair about splitting up the duties.

“My job was to pay for everything,” she says. She also visited weekly with her brother, while a sister lived across the street from their mom and remained on-call. Another sister was a hospice nurse, and got to oversee their mom’s care once she entered into hospice care. But, she adds, “There was one brother who just couldn’t take it. He couldn’t see my mother.”

While elderly parental caretaking so often falls on daughters—one study found that daughters provide about twice as many monthly hours of care as sons—Corcoran gives her brother T a lot of credit for taking the lead in the family. But that, she believes, is because he is gay.

“I love gay men, because they’re more sensitive,” she says, sharing that her brother would even go along with their mother’s delusion that he was their deceased father. “He held out his arms and said, ‘Florrie, baby,’ like my father used to. She thought he was Ed, that he was back, and he’d dance with her to old-fashioned music. That was sad.”

An older member of the sandwich generation, Corcoran was raising the kids she had at 46 (through IVF with a sister’s eggs) and at 56 (through adoption) with husband Bill Higgins throughout her mother’s illness—although she says they were more a source of support than additional stress. “Kids are more open minded and don’t get as depressed about it. They were not unhappy to go see grandmother,” she says about her son and daughter, who were 18 and 8 when she died.

Looking back, Corcoran wishes she had been a bit less stoic when going through the loss of her mother—and advises others not to follow her lead.

“I’ve been through a lot where it’s been extremely emotionally and physically challenging for me to get to where I want to go, but I always felt like I should shore myself up and get on with it. I think it’s a gift to have,” she says. “But I’ll tell you that Alzheimer’s with my mother was really—especially the last four years—I felt sad and I think I was partially depressed. I probably should’ve seen a psychologist. I wanted to help care for her, but I felt burdened and sad. Everybody in the family did. So I think getting somebody to hold your hand is key.”

Today, she has friends who are dealing with parents with Alzheimer’s all alone, which astounds her. “There are so many support groups out there,” she says. “It’s like AA, you know? There’s tons of support groups in every city. Get together and talk about it. That feels so good.” She recommends the online resource RecognizeAlzheimersAgitation.com, a campaign she’s recently partnered with.

Since her mother’s death, Corcoran has also learned a lot about grief. “OK, it’s over. She rests in peace. She’s where she’s supposed to be,” she says, repeating the platitudes she kept hearing from others. “But I didn’t feel it,” she says, still missing her today.