Credit: Jackson Lee/Splash News Online

Sarah Jessica Parker is no ordinary working mother.

In 2011 alone, she's starred in two movies, produced a television show for Bravo and campaigned for a third Sex and the City film -- all while raising son James Wilkie, 8, and twins Tabitha and Loretta, 2.

Because of her jam-packed schedule, Parker quickly realized she can't be everything to everybody -- especially her husband of 14 years Matthew Broderick.

"Kids can really distract you from your relationship," she tells the UK's Telegraph. "Maybe in good ways and bad ways. It's important to have all eyes on all parts of the relationship."

Parker -- who calls herself "an eternal optimist" -- admits her marriage to the 49-year-old actor hasn't always been easy.

"We've been together for 20 years and you have good days, you have decent days, and you have bad days. That's a marriage. That's a relationship. That's a friendship, even -- relationships outside the marriage run the same course."

"If you're in it for the long haul and you want meaningful relationships, you are going to go through lots of different periods."

The New York-based actress tells The Telegraph her list of responsibilities has only grown longer with time.

"Going from one to three children is a much bigger adjustment than becoming a mother in the first place," she says. "One child in retrospect seems a cake walk compared to where I stand today." (Parker and Broderick welcomed their twins via surrogate in 2009.)

"Children provide a whole new set of concerns," Parker, 46, adds. "Who knows what I'll be insecure about next week?"