Sienna Miller On Ex-Fiancé Jude Law's Cheating Scandal: 'One Of The Most Challenging Moments'

Sienna Miller spoke candidly about her “public heartbreak” after her ex-fiancé, Jude Law, cheated on her, describing it as one the most challenging times she has ever endured in her life.

During an interview with The Daily Beast Friday, Miller, 38, revisited the aftermath of Law's affair in 2005. At the time, she had been in London starring in a production of William Shakespeare’s "As You Like It" when it came to light that her then-fiancé had an affair with his children’s nanny.

"That was one of the most challenging moments I hope I’ll ever have to experience," Miller said. "Because with that level of public heartbreak, to have to get out of a bed let alone stand in front of 800 people every night, it’s just the last thing you want to do."

The "21 Bridges" actress said what made the situation much harder for her was that it had happened "at the height of all that paparazzi madness, and in London where there was an epidemic of bad behavior." Miller said paparazzi followed her every time she left her home.

Miller recalled that this period had been so difficult and stressful for her that she blocked it from her memory.

"There’s a whole six weeks of that experience that I don’t remember," she explained. "I have no recollection of it. People who came to see me said we had dinner, and I don’t remember. I was in so much shock over it all. And I’d really just begun. I was only 23. But if you get through that, you feel like you can get through anything."

Miller and Law, 47, met on the set of their 2004 movie "Alfie." They hit it off and got engaged on Christmas Day of that year. But in July 2005, their engagement fizzled out after it was revealed that he had been cheating on her with his children's nanny, forcing Law to issue a public apology.

After their 2006 split, Miller and Law gave their relationship another try three years later but called it quits for the second time in 2011.

Law welcomed his sixth child in September after his wife Phillipa Coan gave birth to their first child together, People reported.

The "Sherlock Holmes" star was previously married to Sadie Frost from 1997 to 2003 and they share three children: Rafferty, 24, Iris, 29, and Rudy, 18. He also has a child with ex-girlfriend Samantha Burke, Sophia, 10. Law and ex Catherine Harding, meanwhile, share 5-year-old daughter Ada.

Miller remains single. She dated actor Tom Sturridge from 2011 to 2015. The pair share 8-year-old daughter Marlowe.

She later got engaged to Lucas Zwirner, but they called it quits in August.

"Sienna and Lucas hit a rough patch in their relationship. Lucas was a bit immature for Sienna," a source told Us Weekly in September shortly after their separation.