I think you should make more allowances re other people's shortcomings, or what you call their "stupidity". Sometimes people just blurt things out without necessarily thinking and/or ask the same thing several times (forgetfulness or just their not paying attention). It does not necessarily mean they want to get at you or "disrespect" you. Do give them a chance...

If you feel offended, do (calmly) ask them what they actually meant. If they meant to hurt you, then you might be justified in being angry. But not bursting out and/or being violent. You only serve to hurt yourself and them in the process. Before hitting out (either verbally or physically), I'd recommend you either take some time out (leave) or give them the benefit of the doubt (asking them to justify their behaviour). Usually, people do not mean any harm but it is human nature to just open their trap and let loose. Your lashing out is not the option.

Anyway, just my two cents.