After twenty years of teaching our language to foreign adults, I too have a schoolmarm in my head who shouts every time she hears a mis-use.
I throw things at the radio when people use "less" instead of "fewer". People ending sentences with prepositions and using who instead of of whom makes me wince.
The times I really want to cry is when people are interviewed on Radio 4 and I can't understand a word they are saying because their conversation is monotone and so peppered with unnecessary garbage that I can't follow the thread. It makes me a bit of a misfit I suppose.