You should read Your Mother's Tongue: Book of European Invective. You'd be surprised (and in your case, probably shocked) at what people call each other without any intention of actually insulting them.

For example, here in Portugal and in informal situations, it's reasonably common for a person to use an expression that essentially calls their mother a whore because they made something that somewhat annoyed you. Of course, no one is actually insinuating their mother sells her body for money, it's just an expression.