Jude Law and Sienna Miller
This is the classic case of straying.
The New York-born model turned actress met Law on the set of Alfie, the movie in which he seduced her onscreen. The romance continued offscreen too and the pair were engaged to be married in 2004.
But this was before a nanny came into the picture (Law had three children from his previous marriage to actress Sadie Frost). Miller found out that he was sleeping with the help, and called off the relationship.
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