Dr. Christina Zampitella, Licensed Clinical Psychologist:
This is a very uncomfortable position for you to be in, and ideally, you could address this situation in a brief, concise way while also maintaining appropriate boundaries between your personal and professional lives... But, it sounds like you really only have two viable options — and both have the potential to get messy. The reason The Office was so funny for six of its nine seasons (yeah, I said it) is because even minor workplace interactions can balloon into a bigger deal than necessary. Here’s my recommendation for dealing with this Facebook fiasco.
Option 1: Unfriend And Ignore
If you’re a non-confrontational person and your first thought is that you do not want to be caught in the middle of this, then put your blinders on and stay out of it. You won’t win any awards for bravery, but you also won’t get dragged into some pointless office drama. Just because your coworker never learned how to create appropriate interpersonal boundaries, it doesn’t mean you didn’t; and if she asks why you un-friended her, just say that you saw some gossip on her feed that you’d rather stay out of. If you’re more “work friends” than real friends, you don’t owe her any more of an explanation than that. Odds are, you might become the subject of one of her rants — but you won’t know about it to worry about it. Problem solved.
Option 2: Make Like A Reality-TV Star & Call Her Out
If her gossip is bugging you and you know it’s wrong, then channel your inner Rosie Perez and do the right thing. Before going to HR, try talking to your coworker directly first. If she trusts you enough to friend you on Facebook (where she likes to air her dirty laundry) then I think it’s fair to assume she places you above mere coworker status. Use this to approach her in a friendly manner and bring up the topic in a way that says, “I’m looking out for you.”