The actress, 63, spoke with the New Yorker about discovering her then-husband had an affair with Helena Bonham Carter, after working with her on 1994's Mary Shelley's Frankenstein, and how she dealt with the aftermath of their divorce.
"I was utterly, utterly blind to the fact that he had relationships with other women on set," she said of Branagh, who she married in 1989 after meeting on the set of Fortunes Of War. "What I learned was how easy it is to be blinded by your own desire to deceive yourself."
The actress and Branagh, once dubbed the Golden Couple by the British press, split after eight years together following his affair with Bonham Carter.
After their split, Thompson "was half alive," she told the New Yorker. "Any sense of being a lovable or worthy person had gone completely," she noted.
Explaining to the outlet that she felt like broken dishes, Thompson went on to note that actor Greg Wise — who she has now been with for 27 years, and married to for 19 of those years — "picked up the pieces and put them back together."
"I've learned more from my second marriage just by being married," Thompson said. "As my mother says, 'the first twenty years are the hardest.' "
Thompson and Wise now have two children together, Gaia, 22, and Tindyebwa Wise, 34. After meeting Tindyebwa when he was just 16 in 2003, a Rwandan orphan, and a former child soldier, he soon became a member of their family.
As for her feelings towards Branagh and Bonham Carter now, Thompson confessed to the Sunday Times in 2018 that despite her heartbreak she has no hard feelings towards them. "That is… all blood under the bridge. You can't hold on to anything like that," she said. "It's pointless. I haven't got the energy for it… Helena and I made our peace years and years ago… she's a wonderful woman."
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Earlier this year, Thompson opened up to PEOPLE about her role in the critically acclaimed new film, Good Luck To You, Leo Grande, and taking on a nude scene for her character of Nancy. In the film, the retired religious studies teacher and mother hires a sex worker (Daryl McCormack) for the night after spending over 50 years doing things by the book.
"Whilst I've never really accepted my own body as anything to write home about, and I've always thought it was not much, not really at all, attractive, nonetheless, I have lived in it and experienced pleasure in it," the two-time Academy Award winner said. "I think the more we can accept our bodies — and not love them, you don't have to love them — but you do have to accept them in order to experience anything inside them."
She also explained that Nancy is ultimately "someone you can relate to," as the widower is on a search for pleasure. In a final scene, Thompson faces the mirror, alone and naked, as her character reclaims her body.
"Emma isn't immune to the culture we are all soaked in which tells us that our bodies will never be enough," director Sophia Hyde shared. "So doing this moment fully as Nancy, having had some access to the greatness of what her body is capable of, Emma had to really trust in that idea and sink into it. Which she totally did."
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Fans of Thompson can also see her take on the role of the iconic Miss Trunchbull in Roald Dahl's Matilda the Musical, which hits theaters on Dec. 9 and arrives on Netflix on Christmas.
In a trailer for the musical, Thompson's Trunchbull can be seen taunting and torturing students. It comes decades after the book was first published in 1988, and the Danny DeVito movie adaptation arrived in 1996.
An official synopsis of the movie describes it as "an inspirational musical tale of an extraordinary girl who discovers her superpower and summons the remarkable courage, against all odds, to help others change their stories, whilst also taking charge of her own destiny. Standing up for what's right, she's met with miraculous results."