Marlo Thomas, 85, on why she didn't want her 'That Girl' character to get married: 'It would have been a betrayal'

Unapologetically is a Yahoo Life series in which people get the chance to share how they live their best life — out loud and in color, without fear or regret — looking back at the past with a smile and embracing the future with excited anticipation.

For actress Marlo Thomas, 85, life is all about doing you. It's a philosophy she's embodied for decades — as evidenced by her sitcom That Girl, which ran from 1966 to 1971.

In the series, Thomas played aspiring actress Ann Marie, who, unlike many of the young women of her time, had no interest in getting married and settling down. Instead, she sought other adventures in life, like a thriving career and life in the city.

"It was the first, and the first is hopefully a launching pad — and it was," Thomas says, referring to the shows that came after That Girl. "There was never a show about a 21-year-old woman, going into the big city, getting away from her parents to live on her own and living her dream. That had never been done. There was a great trepidation as to whether That Girl would be successful — many thought it would not be successful, because it was about a girl without a family … it really had very little going for it. Except, when it hit the airwaves, every household had That Girl on."

Thomas had much influence over the direction of the show, insisting that the series finale not end with a wedding. Instead, the final episode featured Ann Marie taking her boyfriend Donald (Ted Bessell) to a women's liberation meeting.

"Like anything else in life, marriage is a choice," Thomas explains. "And marriage, for me at that moment, was not my choice. I wanted to live a different kind of life. I wanted to be able to travel…I wanted to live out my dream. I didn't want [my character] to get married at the end of the show, because I really felt it would have been a betrayal to all the girls and the women who had followed her, to say that the only happy ending was a wedding."

Thomas did, ultimately, get married. In 1980, at age 42, she wed talk show host Phil Donahue. The two have what Thomas calls a "really good marriage."

"Our relationship is nutritious to me," she says. "We have each other, we're not alone on the globe. That constant communication and listening and talking and cooking together and being together, watching the news together, watching movies together, taking walks together, all of that is part of the fabric of my life. I think having a good companion — whether it's a spouse or not — is very nutritious. You can almost feel it like oxygen into your life."

One another way that Thomas feeds her life is through her work as the National Outreach Director for St. Jude Children's Research Hospital, which was founded by her father Danny Thomas in 1962. This is her 19th year participating in the hospital's Thanks and Giving fundraising and awareness campaign, but for Thomas, her charity work is more than just a philanthropic hobby. Instead, she says, "St. Jude is part of the tapestry of my life."

"It’s a part of me," she says, explaining that she's involved in everything from raising money to learning about innovations in child cancer research from the scientists. She's currently excited about the hospital's new Domino's Village, sponsored by Domino's Pizza, which is a new facility for families of children undergoing treatments at St. Jude to stay. Thomas was part of the design team, and helped bring to life the apartments as well as a "beautiful cafeteria" and play areas for the kids.

"It’s like a neighborhood, and it excites me to know we created this for the families," Thomas shares. "We at St. Jude believe that while we can physically heal the child, we can also emotionally heal the child by bringing the family together."

When it comes to taking care of her own mental health, Thomas says she's a "California girl" through and through.

"I work out five days a week," she explains. "I like to go out in the park. We live near Central Park, and I love to be near the trees. I have a golden retriever named Charlie, and we'll get outside and get a whiff of oxygen and nature and stuff. When I feel blue, the thing I always turn to is outgoing outside. Maybe because I'm a California girl at heart. If I have an argument with someone or I feel bad about something, I bundle up and take a walk. And once I'm in the park and walking with my dog, I feel better."

One other way the star keeps her mental health in check? Not paying any attention to the haters on social media.

"I posted a picture of my husband the other day with his granddaughter and people wrote on my Facebook page, 'Oh, he's had surgery.' Well, no, he hasn't had any surgery…But people think if you look well, you have to have had plastic surgery — and that's not true. But even if you did want to — go ahead! I love what Cher said [when people were commenting on] all of her plastic surgery and this and that. She said, 'It's my body, if I want to put my nose on my ass, I will.' And that's what I love about Cher, she couldn't care less what anybody thinks."

Ultimately, Thomas says she doesn't really "have time" to worry what other people are doing.

"I think we really should allow people to live how they want to live, love who they want to love, and then take care of your own life," she says.

That includes not commenting on other people's bodies.

"If somebody wants to wear a bikini and they look awful in it — that's their choice," she continues. “I have friends who are very overweight and wear bikinis and it's just none of my business — they like how they look. Let them enjoy it! What the heck business is it of mine how they look or what they wear?"

"I'm not into this judging situation, I never have been," she explains. "I didn't get married until I was 42 years old and I got a lot of heat … My friends were already on their second marriages by the time I got married, and I didn't put them down for that. I may never have gotten married if I didn't go on The Donahue Show, and that would be OK too."

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