Poor Sienna Miller.

First she picked up a whole loada flack for her relationship with married father-of-four Balthazar Getty...

And now it seems the fuss and scandal might not have been worth it anyway.

The word on the street is that Sienna and Balthazar have gone their separate ways.

The actress has been living with the 33-year-old millionaire in Los Angeles since this summer.Sienna Miller and Balthazar Getty

The couple were spotted in intimate clinches together on the Amalfi coast last month, and in New York just last week...

But, just as we thought this was the real deal - Si's big love after Rhys Ifans, if you like - there's chat that the 26-year-old has headed back to London for a "cooling off" period.

Insiders say Si's told friends that her relationship with Balthazar is "as good as over" because of his apparent reluctance to file for divorce from his designer wife and mother of his four children, Rosetta Millington.

A source told The Daily Mail:

"She has really wanted to be able to step out as a couple but Balthazar is very torn over his children and it looks like he might be wanting to go back to his family.

"Sienna is devastated. She knows she’s been branded a marriage-wrecker but she swears it isn't the case.

"She says the marriage was over when she and Balthazar met and that he was ready to move on.

"He promised her the earth but he hasn't kept to any of his promises and has made no moves as far as a divorce is concerned.

"Sienna is totally paranoid he is going to go back to his family. She feels very let down by Balthazar."

So is this it for the two unlikely lovers? We'll have to wait and see.