The former couple, who married in September 2008, announced their split in November 2010 and were officially divorced in July 2011.
In an interview with Cosmopolitan, Johansson insisted that she had no regrets about the relationship and had hoped to spend the rest of her life with Reynolds.
"I'm a big believer that when something feels right, you should do it. I'm a big believer in instinct. Getting married was the right thing to do because it was natural," she explained.
"It grew out of a romance and love and a desire to have a future with somebody, and I was very fortunate that I married somebody who turned out to be the person I thought he would be."
However, Johansson admitted that she was not an ideal partner and underestimated the difficulties that the relationship would present.
"Relationships are complicated. Being married is a living, breathing process. I think I was not fully aware of the peaks and the valleys," The Avengers actress said.
"I wasn't prepared to hunker down and do the work... Both of us were extremely busy. We spent so much time apart. It's very difficult."
> Scarlett Johansson jealous of Ryan Reynolds, Blake Lively romance?
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