Stacy Morrison knew the moment her marriage was over.

In 2004, she and her husband, Chris Shannon, were dealing with a new baby, new house and Morrison's new, demanding job as editor of Redbook magazine. Shannon made his frustration crystal clear when he said, "I'm done with this."

"I panicked, and cried and cried," Morrison says. "We agreed that we would try and work on it."

They never said for how long, though.

When she later tried to hold a conversation with her husband, she realized he wasn't listening.

"I said to him, 'If we're trying, can you at least participate?' And he said, 'I'm not trying. I'm waiting for you to be done trying.' That's the day I said OK, the marriage is over."

Shannon moved out 2 1/2 months later. The divorce was final in 2007.

Morrison, the author of "Falling Apart in One Piece: One Optimist's Journey Through the Hell of Divorce" (Simon & Schuster, $26), says her life has changed drastically since then. She resigned from her magazine job to take care of her ailing parents, who are now deceased. She and her ex-husband are navigating the world of co-parenting their son, Zack, now 7. And she's fallen in love again. She and her boyfriend, whom she prefers not to name, have been together three years. No wedding bells yet, but Zack's pushing for it, she says.

Morrison's ex-husband has a key to the Brooklyn apartment she shares with her boyfriend, and he's there at least two nights a week to hang out with Zack and put him to bed.

"Our relationship has continued to change as we've been apart," Morrison says. "It's been a long, slow letting-go process."

These days, Morrison makes a living as a freelance writer and editorial consultant while she keeps up her Website for the book, The book was released in paperback this month.

Morrison discusses the ups and downs of breaking up:

Q: Your book talks about heartbreak, anger, grief and the end of a dream. How did you find the will to write about all that?

A: I wrote the book because I was truly blown away by how hard everything was. To have your life partner look at you and say 'I'm done' instantly makes you question everything about yourself and the life you live and your ability to make good decisions. We're kind of wired to think that bad things happen because we mess up. The whole journey of my divorce was letting go of that and realizing that with life, it just is. ... The lessons that I learned have been such a relief. I walk more calmly in my life. I trust myself much more, and I'm less afraid of change, heartache, disaster. You name it, I expect it -- but not in a pessimistic way.

Q: What did you want after your divorce?

A: At first I thought I wanted answers. Why is this happening? Why is he leaving me? But what I really wanted was peace, clarity, to let go and to not have my divorce be the thing that defined me.

Q: Did you ever feel like a complete failure?

A: Oh, sure. You're kind of dazed in general feelings of suckitude. There's really no avoiding it. ... The way that I got that clarity about peace was self-preservation. There are a lot of feelings going on -- guilt, incredible rage. You feel hate, which is a terrible thing to feel. You feel frightened.

Q: You talk about being on a mission to feel successful in your divorce. Have you achieved that?

A: I say my divorce is the best thing that ever happened to me. You just sort of feel victorious when you get through something hard without creating more damage. I figured out how to honor and respect Chris' experience, thinking, 'Wow, he really feels like he needs to get out of this marriage.' This was his story. It just was affecting me. You go into a marriage together, but it turns out a partnership isn't really a partnership. That's Chapter Two.

But you can let go with grace, even if your partner is kicking, screaming and fighting. Choose the high road.

Q: How does it feel to be in love again?

A: I'm still in a bit of a shock. Having a very serious and committed relationship after divorce might make you feel like you're walking on egg shells. But ... it feels really good. It's been a magical experience, like breathing for the first time. That was such a thrill to not feel like damaged goods. I do not feel like damaged goods. It's made me a stronger, smarter, more compassionate me.

Q: Why do you encourage your readers to be vulnerable and open with their partners through their divorce?

A: When a tree is being buffeted by the wind, the trees that survive are the ones that bend. The ones that are brittle and hard, they snap. We're built to be resilient, but our culture falls in love with being powerful. There is weakness in resilience, but there is also the power to snap back. My divorce brought me to my knees, but I came out with a strong, quiet strength.

Q: How did you come up with the title?

A: I came to my knees, survived and didn't fall into a million little pieces. I want to bring hope to people, not just for divorce, but everything in life. It's about giving over to the hurt, loss and the grief, but it doesn't have to blow you into pieces.

Q: After going through something you never saw coming, what can you say you now know for sure?

A: Life is hard. Life is good. These two truths are unrelated. And we, poor little humans, constantly try to make the connection. You have to live your life by your own internal pilot of knowing where you're supposed to be and to accept the good and bad.