While most divorces – especially those with kids involved – are tough on everyone, it's always made worse when the splits are played out in the public eye.

And with Katie Holmes' divorce from Tom Cruise promising to be a bitter one – with custody of their six-year-old daughter Suri at the centre of the fight – we look back at some of the messier celebrity divorces.

Heather Mills and Paul McCartney

When McCartney and former model Mills started divorce proceedings, Mills asked for £125-million. What for? She apparently needed – among many other things – £176,000 a year for clothes, £650 500 annually for donations to charities, £500 000 a year for holidays, £40 000 a year for wine (yes, wine) and £30 000 a year for equestrian activities – although she rarely drinks alcohol and doesn't ride.

She was eventually awarded a total of £24.3-million, plus annual payments for their daughter Beatrice's care. During the trial, Heather famously poured a jug of water over McCartney's lawyer, shouting "You're a bitch! You're a traitor to your sex!" Classy. After the divorce, McCartney was quoted as saying "There'll be no more nagging, no more chaos, no more Heather... Bliss. I have peace at last."

The experience hasn't put McCartney off marriage for life - in fact, he recently tied the knot with wealthy heiress and businesswoman Nancy Shevell.

Britney Spears and Kevin Federline

When Spears filed for divorce in November 2006, she asked for physical and legal custody of their two children, with visitation rights for Federline. The sometimes- rapper then filed a response against Spears, seeking the same. A global agreement was reached, but shortly afterwards Spears' personal troubles began to escalate. She checked herself into a rehabilitation facility for less than 24 hours, then was pictured the following night shaving her hair off with a pair of electric clippers.

Spears was also photographed attacking paparazzi photographers with an umbrella, she returned to rehab and was charged with hit-and-run and driving without a license.

Although custody was initially shared, a court granted Federline sole physical custody of the children in October 2007. In January 2008, police were called to Spears' home after she refused to relinquish custody of her sons and locked herself in a room with her youngest son, Jayden. She was taken from her home on a stretcher and admitted to hospital after appearing to be under the influence of drugs, and apparently had not slept for close to four days. As a result of this, Federline was awarded sole legal and physical custody – with Spears initially denied even visitation rights.

Spears was placed under conservatorship, and as she began to clean up her act, began to fight for rights to her children. In July 2008, her visitation rights were reinstated – and her next move seems to be to have her conservatorship eased: especially in light of her engagement to her former agent, Jason Trawick.

Prince Charles and Diana Spencer

What was once a fairytale ended in disaster for Prince Charles and Diana Spencer.

At first, the Royal couple managed to keep their marital troubles firmly under wraps. However, once the story was leaked to the media, every detail was sensationalised. Both the Prince and Princess of Wales allegedly spoke to the press through friends, each blaming the other for the marriage's problems.

Diana was revealed to be insecure and Charles inattentive – and each party appeared to have indulged in extramarital affairs. The couple separated in December 1992, and a year later Diana announced her withdrawal from public life.

Diana was famously linked to James Gibley and James Hewitt, while Charles was repeatedly linked to his former girlfriend Camilla Parker-Bowles and his sons' nanny Tiggy Legge-Bourke. While Diana primarily blamed Camilla for the problems in her marriage, she later became convinced that Charles was involved with Tiggy – and that Twiggy had to abort Charles' child.

In a 1994 interview, Charles confirmed his affair with Camilla, but claimed they only reignited their relationship in 1986 after his marriage to Diana had "irretrievably broken down". In 1995, Diana famously gave a frank interview to the BBC, and claimed that there were "three" people in her marriage. She also questioned Charles' suitability for the throne and stated her desire to be the "queen of people's hearts".

As a direct result of the interview, the Queen demanded an early divorce between the couple. On 20 December 1995 Buckingham Palace announced that the Queen had advised Charles and Diana to divorce. Charles immediately agreed, and after negotiations with Charles and the Queen, Diana agreed.

The divorce was finalised on 28 August 1996. Diana received a lump sum of around #17-million, as well as a clause preventing her from discussing the details. The Royal family had wanted an alimony settlement, which would have provided some degree of control over the erstwhile Princess of Wales.

Because she was the mother of the heirs to the throne, Diana remained a member of the Royal family until her death in 1997.

Charlie Sheen and Denise Richards

In March 2005, while she was still pregnant with their daughter Lola, Richards filed for divorce from Sheen. They tried to give their relationship another go and went for marriage counselling, but in January 2006, Richards confirmed that she was continuing the divorce. She also sought a restraining order against Sheen, claiming he had threatened to kill her.

Formal papers were filed in April 2006. Richards claimed Sheen was physically and verbally abusive and threatened to kill her or have her killed. She also said he had become paranoid and obsessive – that he was obsessed with the murder of Nicole Simpson, 9/11 conspiracy theories and believed that baby formula caused brain damage.

Richards claimed that Sheen visited prostitutes and was addicted to gambling, prescription drugs and pornography. She further claimed that Sheen posted pictures of his erect penis on a "sex-search" website, and viewed pornography featuring very young girls and "gay pornography" featuring very young men.

Sheen described Richards' actions as a "smear campaign" and denied all the allegations. The couple were engaged in a bitter custody battle over their two children, but they eventually reached an agreement in an attempt to do their best for their daughters.

The couple have since smoothed things over, with Richards and Sheen even going on holiday together with their daughters. Winning.

Alec Baldwin and Kim Basinger

Baldwin and Basinger filed for divorce in January 2001 after a marriage lasting just over seven years. While the divorce was finalised in February 2002, they have been locked in a bitter custody battle for their daughter, Ireland Eliesse "Addie" Baldwin. In 2008, Baldwin released a book called A Promise to Ourselves, detailing his battle to remain a part of his daughter's life.

He claimed that Basinger had attempted to deny him access to his daughter by refusing to discuss parenting, blocking visitation, not providing telephone access and ignoring court orders, as well as turning his daughter against him. He claims to have spent millions of dollars in an attempt to remain part of Ireland's life.

He refuses to blame his ex-wife entirely, and wrote "She is a person, like many of us, doing the best she can with what she has. She is a litigant, and therefore, one who walks into a courtroom and is never offered anything other than what is served there. Nothing off the menu, ever." Instead, he blames her lawyers and her psychologists.

After seven years of these issues, Baldwin "hit a breaking point" and left an angry voicemail message in response to another unanswered arranged call. He called his then 11-year-old daughter Ireland a "rude, thoughtless little pig" and called Basinger a "pain in the ass".

Baldwin later revealed that he had contemplated suicide after the voice mail was leaked through the press. Of the incident he said, "If I committed suicide, [Kim's side] would have considered that a victory. Destroying me was their avowed goal."

Baldwin's relationship with Ireland has since been repaired – with his daughter being present at his recent wedding to yoga instructor Hilaria Thomas.

Notable mention

Kim Kardashian and Kris Humphries - while only married for 72 days - have spent almost a year on their split: and they're not divorced yet! Humphries claims that Kardashian set up the entire wedding to boost television ratings for her show, Keeping Up With the Kardashians, and is claiming fraud.

We're pretty sure that when this one eventually does hit the courts, it will be messy.