The 38-year-old told PEOPLE on Wednesday that after she grew uncomfortable with her breasts being different sizes, she underwent plastic surgery — but instantly regretted it.
"I was always praised for my body, and I felt like people had expectations from me that I couldn't deliver," Bündchen, said. "I felt very vulnerable, because I can work out, I can eat healthy, but I can't change the fact that both of my kids enjoyed the left boob more than the right. All I wanted was for them to be even and for people to stop commenting on it."
She said how she wrote about the secret 2015 breast augmentation in her new memoir, Lessons: My Path to a Meaningful Life, about her decision.
"When I woke up, I was like, 'What have I done?' I felt like I was living in a body I didn't recognize," she said. "For the first year I wore [baggy] clothes because I felt uncomfortable."
She explained that husband Tom Brady, 41, was a source of support throughout the ordeal.
"He just said, 'I love you no matter what' and that I looked beautiful," she said. "This was definitely another lesson: What doesn't kill you makes you stronger. But I wish I would have learned that a different way."
The famously private Bündchen also opened up about battling panic attacks and suicidal thoughts, as well as the stresses of marriage and motherhood.
"Things can be looking perfect on the outside, but you have no idea what's really going on," she said. "I felt like maybe it was time to share some of 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."
Bündchen and Brady share 8-year-old son Benjamin and 5-year-old daughter Vivian. She is also close with Brady's 11-year-old son Jack, with actress Bridget Moynahan.
Brady and Bündchen have been married since 2009 after Brady proposed in dramatic fashion.0comments
"When he proposed to me, he made up this whole story how my apartment was flooding and I ran over there to try to fix the situation," Bündchen told Vogue earlier this summer. "When I got there, the whole apartment had candles and rose petals everywhere and then he went down on his knees to propose."
And even though he was down on one knee, she said she would have rather he stood. "I'm like, 'Get up!' 'cause he just had surgery and had three staph infections," she said. "I'm like, 'What are you doing?' He's like, 'I gotta go on my knees.' I'm like, 'No, no, no, get up, please!' And here we are."