The law expects people to have a thick skin.  Not every bad thing that someone says about you justifies a lawsuit.  First of all, what is said must be untrue.  Second, it must be more than just an opinion that you are a “bad” person.  It must make a false factual assertion that you have done something illegal or something so despicable, no one would stand still for it.  Being accused of committing a crime or carrying a communicable disease are both grounds for filing suit.  The bar is set higher for famous people, about whom many have opinions.  Accusing Bill Clinton of adultery would not be actionable.  Accusing your neighbor of adultery would be actionable.