The former couple met on the set of their film Firstborn and dated for seven years in the ’80s and early ’90s before calling it quits.
“It taught me how I love,” the Divorce star told PEOPLE and Entertainment Weekly Editorial Director Jess Cagle of her relationship with the actor, who struggled with drug and alcohol abuse during much of their time together, ultimately leading to their demise.
Adds Parker, 51, “And what’s the difference between loving and taking care of people and what’s necessary, and what grown-ups should and shouldn’t do for one another.”
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For his part, Downey has spoken about Parker’s many attempts to help him throughout their years together.
“I liked to drink, and I had a drug problem, and that didn’t jibe with Sarah Jessica, because it is the furthest thing from what she is,” he told PARADE in 2008. “She provided me a home and understanding. She tried to help me. She was so miffed when I didn’t get my act together.”
Although the couple split in 1991 — Parker went on to marry Matthew Broderick and the couple are now parents to 7-year-old twin girls Tabitha and Loretta and son James Wilkie, 13 — the actress says her time with Downey had an effect on the way she parents her children.
“Maybe it taught me a little bit about being a parent too, because the things that I ended up caring about, and the way I cared for Downey, were things that might be more suitable for a parent at a certain point,” continues the former Sex and the City star
“In a way, I think I’m asking myself those same questions now — I have an almost-14-year-old, so what I should and shouldn’t do for James Wilkie is a question,” she adds. “Like, at what point do I let him lose something? When do I say, ‘You gotta lose it in order to understand how to even cope? How are you going to develop your coping mechanisms if I’m fixing?’ ”
“When does a parent let go? When do you let go in a relationship?” she continues. “So I think I learned a lot about it. You don’t know you’re learning about it when you’re in it — you’re just in the day-to-day, caring about someone and loving them, and hopefully keeping them safe.”
The Hocus Pocus star adds that she also picked up some other useful skills during her time with Downey — the latter of whom has spoken positively about his relationship with Parker, and how she tried to help him in the past.
“I also learned how to balance a checkbook because I had to, and I think those are pretty big things to be learning,” Parker says.
— Jen Juneau and Anya Leon