Jude Law has to draw the line somewhere.
An affair with his nanny? Come on, she was hot! But Sienna Miller partying a lot? That's unacceptable.
Indeed, according to the New York Post's Page Six, Law was the one who ended this troubled relationship this time around.
"She was just too wild for him," said an insider. "She partied too much. He is a devoted father of four children and she always wanted to go out constantly. He was just done with her."
The actor was so devoted, of course, that he slept with Daisy Wright - the nanny to his kids - the first time he and Miller dated in the summer of 2005. This prompted Miller to dress exactly like Lindsay Lohan and Nicky Hilton for awhile.
After the publication of Wright's diaries, which detailed her three-month fling with the actor, the two parted ways and Sienna took up briefly with her Camille costar, James Franco.
The on-off couple reunited again last May, but are now over for good, according to friends of the duo. We've heard Jude has his eye on Kristin Cavallari.
But that's only because he reads The Hollywood Gossip everyday.