Embarrassingly, attempting to correct someone's grammar on Facebook by saying "don't is 'do not' you meant dont'" for other people to then say "what? dont isn't even a word" made me realize that I had made up my own word. In my head, "don't" reads as "do not", and so it isn't always applicable or make sense in some sentences! but how embarrassing!
I blame my English Literature teacher last year who beat into us how we should never abbreviate in English - as in English you're marked on your use of language so to use abbreviations like "won't", "isn't" and "i'd" to think of some examples was a complete no-no. This is how 'dont' came about, as "don't" = DO NOT.
Have you ever made up a word and been so adamant it exists? I blame my teacher! How embarrassing though, to try to correct someone and say something wrong yourself..