Like many celebrities, Sienna is private about her personal life, but several of her notable relationships unfolded in the public eye. After starring in the film Alfie with Jude Law, the pair began dating and quickly became engaged on Dec. 24, 2004. However, in July 2005, Jude issued a public apology to Sienna for having an affair with the nanny of his children. The couple attempted to salvage their engagement before officially breaking up in 2006.
Source: https://www.distractify.com/p/sienna-miller-husband