Bridget Moynahan on the Painful Scrutiny of Her Breakup with Tom Brady and How They Co-Parent

Bridget Moynahan is opening up about one of the most difficult times in her life — and the inspiration came from a pair of shoes.

“I think a lot of women can relate to finding themselves in a life moment that has taken a little bit of their joie de vivre out of them, and then having that moment to reclaim it,” she says about sharing her very personal story in her new book, Our Shoes, Our Selves, an anthology of essays from women ranging from the late Barbara Bush to Tammy Duckworth to Katie Couric about the personal meaning of their favorite pair of shoes.

In the book, written with Amanda Benchley, and for which she will donate a portion of the proceeds to the charity Girls, Inc., “the women wrote about the heels that made them feel sexy, or combat boots that had jumped out of airplanes,” Moynahan tells PEOPLE this week’s issue, on stands Friday. “But the stories all represented a moment that affected them and put them on another path.”

RELATED: Gisele Bündchen Opens Up About Her Blended Family with Tom Brady: ‘I’m So Grateful’

Her own deeply personal essay calls back to her most vulnerable time. It was 2007, and Moynahan, then 36, was expecting a baby with her ex-boyfriend, New England Patriots quarterback Tom Brady, after he had already moved on with supermodel Gisele Bündchen.

The firestorm of controversy that ensued meant that the actress, then best known for roles in I, Robot, Coyote Ugly and Sex and the City, was suddenly a tabloid fixture.

“Being pregnant and having a baby are such personal, intimate moments,” she says. As she faced an unexpected life as a single mom to Jack, now 11, and navigated the relationship with Brady and Bündchen, Moynahan says the public scrutiny became too much.

“I would have cars following me, and men hiding in the bushes outside my house,” she says. “As a new mother, you want to just protect your child. That kind of attention felt like a threat.”

Then one day at Barneys — where she was hiding from photographers who had followed her while she returned baby clothes — she spotted a pair of motorcycle boots. “I thought, that’s what I need. Let me get a little bit of my ‘New York’ back, a little armor,” she says.

• For more on Moynahan, pick up this week’s issue of PEOPLE, on stands Friday

These days, Moynahan says she is grateful that she’s been able to give her son a safe and private life, along with her husband of three years, businessman Andrew Frankel.

And she also feels lucky she and Brady have been able to co-parent successfully.

“Tom and I made a decision to raise a child together and we both found partners that not only supported us in raising that child, but also loved our child as if he was their own,” she says. “I don’t think you can ask for more than that. My son is surrounded by love.”