Your facebook page is like your own home. That's your space. You do, say and display what you want there. Anything posted on your Facebook wall is like a picture or poster you hang up in your bedroom. If someone doesn't like seeing it, then they don't need to go there. Friends have the option to "unfollow" you, if they don't like what you put up. No one's forcing them to look at your stuff.

You can block visitors, but I would use a different tactic first. Simply delete any comments that are just people giving you grief. When they see their comment gone, they will get a "lesson." Those who don't learn can be blocked. No one has a right to disrespect you on your facebook space.