I have a FB account that I use strictly for real life friends (that I've met and know in person/real life). I don't like to link it to ILs strictly because that kind of relationship to me is different to friendships. I love my ILs, don't get me wrong, but it's not the same kind of friendship.
Tonight we started talking about FB and H said that he had a FB account. He only has it 'cause once I forwarded him a link to an article that I thought would interest him, and he had to create an account to read it. He never posts a thing. But he told them that yeah, he had an account and then they asked me (quite naturally) if I did. I told them that yes, I had one, and they asked if I'd friend them. I then told them that I don't have relatives on there, just friends and I prefer to keep it that way. They seemed to understand but I'm not sure... they could have been hurt and if they were, I'd get it (although I don't think they would be). SIL did ask, though, "So you don't have your sister or your father on there?" and I replied that no, I didn't, and I didn't think they even had FB accounts.
This lead me to wonder - do you have your families and ILs on your FBs (if you have one)? Do you have a policy about the types of relationships you friend and if so, how do you enforce that policy? Up till now, I just haven't told anyone that I have FB (and I use a variation of my name on there) but ... anyway, just curious.