Feeling sorry for Heather Mills is not easy. Call girl, porn model, fantasist, gold-digger, publicity-seeker - these are all allegations that have stuck to Sir Paul McCartney's estranged wife.

But, right now, Lady McCartney (as she still likes to be known) is certainly feeling very sorry for herself.

Sources have revealed that Christmas went out with a distinct bang for Heather, thanks to a fiery argument with Paul, who has recently undergone a serious but routine coronary angioplasty to unblock arteries in his heart.

Strong words were exchanged when the couple met to exchange Beatrice, their four-year-old daughter, after she spent the day with her dad.

It didn't take much to spark the argument - which took place out of Beatrice's earshot.

A source revealed: "It all started at the handover of Beatrice. Paul said to Heather, in what she thought was a sarcastic tone: 'Happy Christmas.'

"Heather replied: 'Happy f***ing Christmas!' And with that she laid into him, saying she thought he'd ruined Beatrice's Christmas by not settling [the divorce] by now.