It used to be the tell-tale lipstick¹ on the collar. Then there were the give-away texts that spelled the death knell² for many marriages.

过去，妻子可能从衣领的唇印发现丈夫出轨。后来，泄密短信也成为诸多婚姻解体的导火索。

But now one in five divorces involve the social networking site Facebook, according to a new survey by the American Academy of Matrimonial Lawyers.

A staggering（蹒跚的，令人惊愕的） 80 per cent of divorce lawyers have also reported a spike³ in the number of cases that use social media for evidence of cheating.

Facebook was by far the biggest offender⁴, with 66 per cent of lawyers citing it as the primary source of evidence in a divorce case. MySpace followed with 15 per cent, Twitter at 5 per cent and other choices lumped together（合并，组合） at 14 per cent.

The survey reflects the findings of a UK law firm last year showing that 20 per cent of its divorce petitions（请愿） blamed Facebook flings.

‘The most common reason seemed to be people having inappropriate sexual chats with people they were not supposed to,’ said Mark Keenan, managing director of Divorce-Online.

Friends Reunited faced similar claims when it was launched to help people reconnect with old classmates, but the 23 million plus people now using Facebook in Britain means it is having a much bigger effect on rising divorce rates.

‘Desperate Housewives’ star Eva Longoria recently split from her basketball player husband Tony Parker after alleging⁵ that he strayed（失散，闲荡） with a woman he kept in touch with on Facebook.

‘Going through a divorce always results in heightened levels of personal scrutiny⁶（监视，审查） . If you publicly post any contradictions（矛盾，反驳） to previously⁷ made statements and promises, an estranged⁸（疏远的，不和的） spouse⁹ will certainly be one of the first people to notice and make use of that evidence,’ said American Academy of Matrimonial Lawyers President Marlene Eskind Moses.

‘As everyone continues to share more and more aspects of their lives on social networking sites, they leave themselves open to much greater examinations of both their public and private lives in these sensitive situations,’ she added.

Marriage counsellor Terry Real said he believes some users go on Facebook to create a fantasy life and escape the drudgery¹⁰（苦工，苦差事） . But he said Facebook is not really to blame.

‘Before it was email, then before that it was the phone. The problem is not Facebook, it is the loss of love in your marriage,’ he said.