Sarah Jessica Parker on What Makes People 'Bail' in Marriages

Sarah Jessica Parker knows a thing or two about relationships.

The 51-year-old actress is executive-producing and starring in a new HBO show, Divorce, and in a candid new interview, talks about what makes a marriage work, and what makes it fall apart. Parker has been married to actor Matthew Broderick since 1997, but was also an icon for single girls everywhere thanks to her beloved role as Carrie Bradshaw on Sex and the City.

"For me, it's really the investment in the other person," Parker tells Marie Claire about maintaining a marriage. "And it's the expectations you have. They change and you get smarter, and maybe you think those expectations aren't worth striving for with this person, and that's when people bail."

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When it comes to her own personal life, she and her hubby are still going strong after 19 years of marriage. Parker and 54-year-old Broderick have three children together, 13-year-old James and 7-year-old twins Loretta and Tabitha.

"I'm so desperate for my children to be curious people," Parker says. "I just want them to be happy and curious."

Other hot topics Parker opens up about for the magazine's September issue are feminism, and the gender pay gap that's been getting Hollywood talking.

"I am not a feminist. I don't think I qualify," the mother of three says bluntly. "I believe in women and I believe in equality, but I think there is so much that needs to be done that I don't even want to separate it anymore. I'm so tired of separation. I just want people to be treated equally."

"I would like all of that nonsense to end," she adds about men getting paid higher than women for equal work. "I would like women to get paid for the value of their contributions, not by old-fashioned ideas about gender."

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ET sat down with Parker in May to chat about her highly anticipated return to HBO, when she dished about her own healthy marriage, despite her new show revolving around a couple going through a long, drawn-out divorce.

"It was an area of particular interest for me because I'm married, and I love being married, and I'm happily married," she said. "We know almost nothing about people's marriage, because even those who we're most intimate with in friendships, we don't always share the good or the bad. And I just think that at a certain point, some people feel alone and lost."

"I think we're at an age where a lot of people have experienced it, or are about to, or want to, or secretly wish they could, or [are] so grateful that their marriage isn't at that state," she added about the concept of divorce. "And so I love the idea of telling that story."

Watch our exclusive chat below:

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