"I never thought it would happen to me. Nobody does," Eastwood said during a recent appearance on Bethenny Frankel's talk show.
The 48-year-old former television reporter said she was surprised at how hard the breakup hit her.
"I'm not a crier . I don't get shaken up by things," she said, adding that her plan now is to "not cry three days at a time."
"I think I'm on day four," she told the audience to applause.
Eastwood said once she realized that she and Clint would be separating after 17 years marriage, she thought they would have a "smooth" "reentry into the world."
Instead, she said, "stuff started happening in the spring that threw me for a loop. I had no clue that there would ever be any kind of turbulence or bizarre things occur. I thought it would just be really cool, that we'd live in the same town and go to the same place to have a drink. I didn't get it."
Eastwood realized then that her marriage to the 83-year-old actor-director was over.
"That is why I filed for divorce. I think maybe a part of me was holding out, like 'What are we doing here?' Then there have been some definite signs that we're not going to get back together so let's move on amicably is my opinion, but I think there is a mental chokehold on you when you don't have something in place that shows you are definitely apart."
She still has kind words for her ex.
"He's lovely, he hasn't done much. It's other people around him have done things that have blown me away and again my future ex-husband has done nothing [wrong]," she said. "He's probably the sweetest guy I've ever met. He is the sweetest, he is a loving, kind, low-key person so my intuition was still great on marrying a good person."
She said Clint recently took their 16-year-old daughter Morgan to Coachella, along with her 20-year-old half sister Francesca Eastwood.
"I mean he is 83 years old and he's rolling with our 20- and 16 year-old at Coachella," Eastwood said. "He does fun stuff like that with them so they are getting a fun version of dad and a more chill version of mom and life is good for the kids. They are pretty happy."