A study of college students found that the more time they spent on Facebook, the more likely they or their squeeze got jealous about the information posted there, leading to more time spent on Facebook and further fueling jealousy.

Facebook could tank your relationship, says the study in CyberPsychology&Behavior, though obviously Facebook (not to exclude Twitter,  though 140 characters is too short to say anything meaningful) is a catalyst and not the source of the problem.

Amy Muise, MSc, Emily Christofides, MSc, and Serge Desmarais, PhD, from the University of Guelph (Ontario, Canada), surveyed young adults involved in romantic relationships and found that those who spent time on social networking sites such as Facebook may be exposed to information about their partners that makes them jealous, leading them to spend more time involved in online surveillance and to uncover even more jealousy-provoking information. 

They describe a cycle in which Facebook usage and feelings of jealousy became intertwined and had a negative influence on behavior and relationships. Some participants in the study described their increasing use of Facebook as "addictive." The authors recommend further research to explore this feedback loop and to determine whether a similar relationship between online social networking and jealousy toward a partner affects older adults as well. 

"This research on university age individuals is an excellent starting point to begin asking additional questions on how this new forum might be impacting the dynamics of adult relationships and other social processes," says Professor Dr. Brenda K. Wiederhold, Editor-in-Chief of CyberPsychology&Behavior.

Article: "More Information than You Ever Wanted: Does Facebook Bring Out the Green-Eyed Monster of Jealousy?", CyberPsychology & Behavior, Volume 12, Number 4, 2009, DOI: 10.1089=cpb.2008.0263