Remember this when they try beat you into submission by claiming you are not smart enough, or simply an idiot. This is not what they really think of you on the cognitive level, in reality they are afraid of you, and thus you must be 'destroyed'. Their very self-esteem depends on it.
With that in the back of your mind, you can only feel sorry for them. Don't think too bad of them, but make sure you don't suffer yourself either by letting them get to you.