Sometimes partners catch their spouse in the act of sending flirty emails or messages and decide to call it quits.  Some are turning to a growing market of software that helps suspicious husbands or wives track their spouse's online activity.

In other cases the divorce was happening with or without the site, but partners are being shocked to find out online that their partner plans on divorcing them.  Emma Brady, who works as a conference organizer, only found out that her husband was planning on ditching her after he posted a Facebook profile change and she received a status update informing her that "Neil Brady has ended his marriage to Emma Brady."

The lawyers' statements are supported by a recent study by social psychologists at the University of Guelph in Ontario.  In the study, entitled "More Information than You Ever Wanted: Does Facebook Bring Out the Green-Eyed Monster of Jealousy?", they discovered that Facebook leads to increased suspicion and distrust in relationships.  They also found that users get in a feedback loop where their increased surveillance leads to them discovering suspicious looking activity, which in turn leads to more surveillance.  Some users used the word "addiction" to describe how they felt about their compulsive monitoring of their lovers' pages.

Facebook isn't the only site or service that's involved in marriage problems.  Other social networks like Bebo and MySpace are causing similar problems.  And online games such as Second Life and World of Warcraft are also posing a problem as people try to decide the acceptability of their spouse engaging in a virtual relationship.

Amy Taylor, 28, split up with her husband David Pollard after she found that he was frequenting a Second Life escort.

Another growing trend is infidelity arising from reunion websites.  Sites like Classmates.com and Friends Reunited are helping people get back in contact with old friends -- and sometimes former flames.

There's approximately 105 million Facebook users in the U.S. (about 1 in 3 people has a Facebook account) and MySpace has about 50.2 million regular visitors.  In the UK there's 14 million active social networking users.  Worldwide, there's over 11 million World of Warcraft users and Second Life boasts over 7 million unique users with repeated logins.

Meanwhile, divorce rates have dipped slightly from record highs, currently standing at about 40 percent in the U.S. and the UK.  Marriage rates as a whole, though, have dropped, which may help explain why the divorce rate has also dropped.