Sienna MillerSienna Miller has reportedly on the verge of finishing with boyfriend Balthazar Getty after just five months together.

The couple were first linked in June - before Brothers and Sisters star Balthazar confirmed he’d separated from his wife Rosetta - and over the summer, were rumoured to be looking for a home together in Los Angeles.

However, after a holiday on the Amalfi coast in Italy last month, sources close to the The Edge of Love actress told the Mail on Sunday that things are tense between the pair.

The source explained: “Sienna is back in London to give them both some cooling-off time. They are still together at the moment but she has said things aren’t good. There have been some pretty unpleasant rows, largely over Balthazar’s reluctance to commit.

“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.”

The source added that despite fleeing to the US to escape media attention in London, Sienna has missed the social side of life in the city: “Sienna has been missing her party lifestyle. She has come back to have some fun and forget about Balthazar for a while.”