I'm a law student, so obviously I care about words and word choice quite a bit. My mother...not so much. She has an approximation for everything. She refers to the tv show The Middle as "Stuck in the Middle" and calls the Bamboo Garden restaurant near us China Garden. Sometimes it's minor stuff like the names of tv shows and restaurants, and other times she has an approximation for names and descriptions for things like my brother's official job description or the classes I'm taking. I just got done with a mock trial competition involving a motion for summary judgment. Because of the way my mother conveyed this to my grandmother, said grandmother called me to ask me about the "court date competition". For pronunciations, she gets one idea of the way a word is supposed to sound stuck in her head and refuses to change. Sometimes it's pretty embarrassing to be in public with her if she keeps pronouncing things like "acai" and "rooibos" the way she does. When she refers to "rayobis" tea no one has any idea what she means.
When I gently correct her and say "Mom, it's Bamboo Garden" she gets indignant. She insists that it doesn't matter because everyone knows what she means. When I bring up the fact that a lot of people don't, especially if she's approximating restaurants to new arrivals, she brushes it off. I've tried telling her that words matter to me, but she doesn't care. I'm not alone in this, my dad actually feels the same way about it.
(By the way, my mother's mental health isn't deteriorating. The stuff she approximates isn't foreign, complicated, or anything that's she's heard about less than a hundred times. She just refuses to make herself learn the correct names and pronunciations for some things.)