What do you mean by “highly personal?” I didn’t deactivate mine but I did take some steps to ensure that I’m not going to get in trouble if someone (coworker, admin, parents) finds it.
— I changed my name to my first and middle name instead of my first and last name. I’m lucky enough that all parts of my name are pretty common, but not everyone is. Some people I know also abbreviated their name or sounded out their name (Jay Son Smith, as an example).
— I took all the steps to make my profile as unsearchable and private as I could. I made it so that all of my pictures are for friends-only viewing. I disabled all search capabilities I could. I’ve always had these settings, though. My friend also has super strict settings. It took us a year to find each other. No joke.
— I deleted/untagged a TON of pictures. I also made the switch to have to approve all tags my friends make. So when my friends tag me in a status about where we are, or a picture, or whatever, I have to approve it. It’s kind of an annoying step, but I’m glad to do it so that I don’t have anything scandalous on there. I never had any pictures of me actually drinking or being stupid, but I’m also worried about the fact that I took pictures in a bar on my 23rd birthday. Be super careful about what you post on it.
Some of my friends deactivated their profile for a while, so that way you can come back to it if you want.
Also not necessarily Facebook related, but I keep my personal and education-related Tumblrs separate. I would love an admin to see my education-related Tumblr and would probably be super embarrassed to have him/her see my personal blog where I fawn over pretty people.