Most of us were pretty shocked when tabloid headlines claimed that songbird Mariah Carey was suing billionaire former fiancé James Packer for breaking her heart!

The couple called it quits last September, following what sources say was a "dramatic fight" while on holiday in Greece. Mariah was reportedly so devastated she cancelled a leg of her tour and could not perform due to the "emotional trauma" she suffered as a result of the breakup.

But Carey is not taking the heartbreak lying down. She allegedly filed a lawsuit demanding $50-million (R650-million) from Packer, claiming that she uprooted her life and her kids from New York to be with Packer in Lost Angeles during the time of their engagement, while his kids were close by.

Packer also allegedly made many financial promises to Mariah during their brief love affair, which were never fulfilled.

She now wants financial compensation for all the time and effort she put into the relationship, and the two will battle it out in court soon.

Most people probably rolled their eyes and dismissed Carey as being a diva when they read the headlines. Who actually sues their ex for breaking their heart? And what are the success rates?

Here at home the only notable case was when Xoliswa Ngema took former MTN boss Sifiso Dabengwa to court claiming that a ring he had given her signified that they were married and demanding half of his reported R200-million fortune at the time.

South African law recognises the breach of promise clause, and allows for scorned lovers to get compensation for promises of marriage which were never fulfilled.

Sipho Nkosi, an attorney at Modise Attorneys Incorporated in Krugersdorp on the West Rand, explains the law.

How does one actually go about suing an ex-lover?

"There needs to be proof of an engagement, either an engagement party, the purchase of a ring, photos of the engagement party perhaps. If you have witnesses who can testify to the fact that you were engaged, that would even be better for your case. It needs to be an impartial and unbiased witness, though, and who can testify that indeed an engagement took place. It also helps if both your families knew about your engagement.

"What most people do not know is that when you ask someone to marry you, it is seen as a contract by the law, almost like marriage is a contract. So it is your duty to fulfil that contract, and the only way to fulfil it would be to marry the person you promised marriage to. If you don't, you are violating the contract, and the person can sue you."

Nkosi says you cannot back out of an engagement without a valid reason, and that falling out of love is not seen as a legitimate reason by the court.

"This is the reason you have to be absolutely sure before you ask someone to marry you. Of course, there are some reasons that the court will take into consideration for wanting to pull out of the engagement, and these include if you found out that your fiancé is cheating on you, for example, or if they are being abusive or involved in illegal activities."

Most people are under the impression that women are the ones who mostly sue for breach of promise, but Nkosi says that he recently had a male client who he assisted to sue his ex for breach of promise

His client filed a lawsuit against his fiancée for R100000 for the humiliation he suffered when she ended their engagement, and won the case.

"A big factor in winning a breach of promise lawsuit is your standing in the community. If you are very well known, the humiliation you will suffer can be emotionally damaging. Most people do not sue for the sake of wanting the money. It is about the principle and the damage done to their reputation."

Nkosi says that one has three years from the time the engagement was called off to file a breach of promise lawsuit.

So does Nkosi think that Carey will win her case? He says he is almost certain that she will.

"If she can prove her allegations that she cancelled tours and uprooted her family, she has a strong case."