Twitter, Facebook, blogs and all the other online connections make it so easy to share your thoughts and feelings with the rest of the world. Maybe too easy. Experts say that social media postings are increasingly being used as evidence in divorces, custody and visitation cases.

More and more people are learning, to their dismay, that nothing really disappears from the Internet and even those companies that promise to clean up a sketchy online reputation can't sweep the dirt out of the darkest crevices of the web. Sure, it feels great to unload invective on a former or soon-to-be former spouse but legal experts say it's best to heed that old adage; if you can't say something nice don't say anything at all. Posters give up their rights to privacy and, as they say on the TV police shows, everything you say can and will be used against you in court.

So where are the red lines? Calling your ex an idiot is an opinion, and that is protected by the First Amendment. But calling a person a deadbeat, a drunk, a drug user, or anything that, in the words of legal scholars, "reflects unfavorably on someone's morality or integrity or discredit a person in his or her occupation" is not protected. Write the wrong thing and a defamation suit could be dumped on top of the family law case.

Rest assured that law firms use consultants and software tools to collect online information that helps their client and damages the other person's case. A lengthy and intensely personal online rant may have felt good at the time, but imagine seeing a transcript handed over to the judge at the next court session. No judge is going to grant custody to someone who seems to have anger management issues. Get sound legal advice about how to stay out of online trouble during a custody case. If there's a lot out there already, an experienced family law attorney can develop strategies to counter the perceived character presented in the online posts and help the court understand the person behind the postings.