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Emma Thompson and Kenneth Branagh were once the star couple of British theater and cinema, drawing comparisons to Elizabeth Taylor and Richard Burton.

The actors cited work demands when they separated in 1995 after six years of marriage, though there were persistent rumors at the time that Branagh was having an affair with up-and-coming actress Helena Bonham Carter.

Now, 18 years later, Thompson, 54, is speaking about the breakup of her marriage for the first time.

Borrowing a phrase from director Mike Nichols, Thompson told The Sunday Times, that it's "all blood under the bridge."

"You can't hold on to anything like that," Thompson said. "I just think… pfft. It's pointless. I haven't got the energy for it. Helena and I made our peace years and years ago."

Thompson told the newspaper that she and Bonham Carter, now 47, her co-star in 1992's "Howards End" and the "Harry Potter" films, have a number of similarities, including "being slightly mad and a bit fashion-challenged."

"Perhaps that's why Ken loved us both. She's a wonderful woman, Helena," she said.

Thompson met Branagh in 1987, on the set of the BBC mini-series "Fortunes of War," and they married two years later. She is now married to actor-producer Greg Wise and the couple shares 13-year-old daughter Gaia, and adopted son Tindyebwa Agaba, 26.

Branagh's relationship with Bonham Carter lasted until 1999. He wed film art director Lindsay Brunnock in 2003, while Carter has been in a long-term relationship with director Tim Burton since 2001, and they have son Billy, 10 and daughter Nell, 5.