Gisele Bündchen made motherhood look effortless and glamorous in a now-famous Instagram photo of herself breastfeeding then-1-year-old daughter Vivian while on the job in 2013.
But in her memoir, Lessons: My Path to a Meaningful Life, written in the style of a journal, the famously private supermodel reveals that motherhood was a tougher adjustment than her enviable Instagram photo let on.
“Things can be looking perfect on the outside, but you have no idea what’s really going on,” Bündchen, 38, says in a revealing interview in this week’s issue of PEOPLE, on stands Friday. “I felt like maybe it was time to share some of my vulnerabilities, and it made me realize, everything I’ve lived through, I would never change, because I think I am who I am because of those experiences.”
After marrying New England Patriots quarterback Tom Brady, 41, in 2009, Bündchen welcomed their son Benjamin (now 8) that same year, and daughter Vivian (now 5) three years later. (Bündchen is also close with Jack, 11, Brady’s son with actress Bridget Moynahan, whom she calls her “bonus child.”)
Together, they’ve always appeared to be the picture-perfect family. But the fiercely independent Bündchen admits now that the transition initially left her feeling lost and confused.
“When I became a mom, I kind of lost myself. It was like a part of me died,” she says. “I’d been this very independent person. It was all about me. But now I had this little being, and I suddenly felt l couldn’t do other things and that was very hard for me. All I ever wanted was to be a mom, but when you’re actually experiencing that, it’s a shock.”
Though she scaled back on work to stay close to home (she had relocated from New York to Boston, where Brady plays), “I had all this horrible, self-imposed guilt. I thought what a terrible mother I was for leaving my child even for like a day,” she says. When she would bring her children along on jobs, “I was feeling guilty for that too. Like, ‘Here we are on a plane and the baby is crying.’ ”
Bündchen also acknowledges that the stresses of parenting have sometimes taken a toll on her marriage.
Taking on the majority of the childcare while Brady trains — often from 6 a.m. to 6 p.m. — “You’re overwhelmed and tired and then you’re not the nicest partner,” she admits.
For more on Bündchen’s book, pick up the current issue of PEOPLE, on stands Friday.
Bündchen says she and her husband have had disagreements (his decision not to retire, for one), and weathered rough patches (like 2015’s Deflategate scandal, when Brady was suspended while NFL officials investigated allegations that he cheated by playing with under-inflated footballs).
“When someone you love is happy, it makes you happy, or if they’re sad it makes you sad,” she says. “You suffer with them and you have joy with them.”
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Together, they’ve learned how to handle the tensions. Bündchen recalls a rough time when she and Brady were in different countries, and he sent her an email she characterizes as “angry.” Rather than respond in kind, she put her fury on paper and decided to burn the pages.
“Then I told him I was ready to speak whenever he was ready to resume the conversation in a loving and respectful way,” she recalls. They rebuilt from there, and, she says, “Tom has read my book but he didn’t ever ask what was in that letter [I burned]!”