It's addictive if you want/need to be social. My wife does, not me. I'm not a very social guy honestly, I have a few friends in my inner circle who I text/gchat/fb messenger with but I don't use the facebook app or the web interface.

Since I deactivated my acct in Dec last year to focus on bschool apps, I've accomplished so much, and I say that not to brag, but to illustrate that it was a bit of a timesuck for me and I've been able to do a lot more since I quit.