The Brazilian beauty famously dated the "Titanic" hunk from 2000 to 2005, during which they travelled everywhere together, and even enjoyed a date night at the 2005 Oscars - marking the only time to date that DiCaprio has ever taken a girlfriend to Hollywood's big night.
However, fans were left stunned when it was revealed the superstar couple had split, and now Gisele, who is known to keep her personal life private, has shed some light on the reasons behind her difficult decision in her new cover story for PORTER magazine.
"No longer numbing myself with smoking, drinking and too much work, I was becoming more and more aware of things that I'd chosen not to look at," she explains. "Was I alone in wanting to do some serious soul-searching while he (DiCaprio) stayed the same? In the end, unfortunately, the answer was yes."
Gisele ended up finding love with American football star Tom Brady after they began dating in late 2006, and now the couple, parents to nine-year-old son Benjamin and six-year-old daughter Vivian, will celebrate its 10th wedding anniversary later this month.
But the stunner, who quit walking runways in 2016, reveals that while she may be one of the biggest names in fashion, it's actually Tom who is really passionate about his wardrobe.
"I'm a jeans and T-shirt kinda girl," she confesses. "If you see me once a year at the Met (Ball) dressed up, it's because I have to wear a dress, otherwise I'd show up like this."
"It's so funny. Tom actually loves clothes more than I do. Sometimes I'm like, 'What is all this clothing that is showing up at my house?' He just loves it. The only time he asks me advice about clothes is when we go to the Met Ball, and he wants to coordinate with what I'm wearing."
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Five years ago, when PORTER launched globally, supermodel @Gisele covered the first issue, accompanied by a coverline that read: INCREDIBLE WOMEN. The magazine has always been – and will continue to be – dedicated to inspiring women, those featured within its pages and those that read them. Now Gisele returns to celebrate our birthday with a very special shoot and interview, opening up about the crisis that led her to rethink her entire life, her husband @TomBrady’s love of fashion and the power of female solidarity. Photographed by @mario_sorrenti and styled by @georgecortina Gisele poses in SS19's white-hot pieces in a series of images that reveal exactly why she is one of the most iconic models of all time. More pages of #IncredibleFashion unfold through a daring new look for spring: sculptural silhouettes captured in Rio, tailored power pieces as seen on 75-year-old top model #LaurenHutton, dramatic color-blocking for your next escape, and head-turning jewelry. Then we celebrate the #IncredibleWomen who have given their voice to PORTER since its launch, as we ask them to reflect on this last half decade and share their ideas and advice for the five years ahead. PORTER's anniversary issue lands on global newsstands 8 February. #5YearsPORTER #IncredibleWomen #IncredibleFashion Editor-in-Chief: @lucy_yeomans Fashion Editor: @georgecortina Gisele wears dress by @chloe
Gisele will likely be rocking her favourite low-key look this Sunday, February 03, when she and her family cheers on quarterback Brady and his New England Patriots teammates at the Super Bowl in Atlanta, Georgia. They will face off with the Los Angeles Rams for the American football championship.