I'm not a big fan of Facebook myself. Not sure why it's become such a big deal, and actually, I mainly use it to just play on literally TWO game apps on there, which takes me...what, all of 10 minutes? Only when I have some spare time, so it's not everyday either. I tend to check around on MySpace more, but either to update (usually if something significant has happened), or if I get notifications via e-mail.
I've been tempted myself to delete my Facebook account on a few occasions, as it's made me feel crappy before, but now I just tend to ignore it for the most part. In your case, you might just be better off deleting it if you don't really use it. Like, if you talk to those people that you have added on there now, outside of Facebook, then you don't really need Facebook, especially if it's making you feel that way. However, if you do get SOME use out of it, and would like to use it on an "alert basis" (in other words, only check it if you get alerted via e-mail), then keep it.
Also, I found this video hilarious: