You know what's strange? My son would curse up a storm sometimes around the house (and me). He knew my thoughts about swearing but I tried to be a little tolerant if he was trying to get something out, but not if he ever swore AT me.
That said, when we were with any of his friends, if I'd visit or if we were taking some to a meeting, and they swore at all, even mildly in the car, my son would turn to them and say "Don't use language like that around my mom!"
He KNEW better but didn't DO better on his own. Go Figure.
Hugs