PLEASE HELP! co workers and social media

I been working at my yob a year not that long and Switched departments as soon as I Started the Whole department friended me on FB and I accepted (I really shouldn't have?) Drama started with someone bumping me out of my department with more seniority then people started talking about it (me) Don't get me wrong they all pretend to be so nice and concerned but really not. I Really don't feel comfortable having any of them on my business on social Media. It's about 5 or 6 of them some even Started acting different toward me when they became my friend.

One coworker friended me last year this year he must have unfriended me and maybe blocked me don't know why I only put positive things and family vacay on my fb

so would it be wrong to unfriend and block the 5 Other coworkers?

Please help!