Tell us something we don't know.
A recent study confirms that excessive use of Facebook can be detrimental to the ol' self-esteem. In the study, folks who already felt like crap about their lives tended to post negative feelings and events to the social network, which made their "friends" hesitant to interact. In turn, the Debbie Downers felt sad and unloved, creating a sort of domino effect. But those happy with their lives were more apt to post positive status updates. Despite that difference, both groups were apt to feel like doo-doo when comparing aspects of their own lives to the social lives of others.
That said, take this poll while I peruse my pal's happy honeymoon pics and have a good sob.