You can hide people from your news feed by clicking on their name. You will no longer see their status updates and such, without having to delete them. You can also untag yourself from pictures, BUT since you are in them if you ask them they should take them down. If however, you don't want to do that just untag yourself.
Something I ended up doing was de-activating my account for a while. I deleted whom I no longer wanted to be in contact with when I came back and guess what? Most of them didn't even notice...