I think I would have just let it go, couldn't care enough about what such a person thought. We have a friend who regularly says things in an assertive way which we know are wrong but we just say what we know to be the fact and then let it go and very often some time later she says what we said in the first place. We don't know if she goes and checks and doesn't admit she is wrong or whether she has taken on board what we say but just not given to admitting she was wrong. Not very bothered really unless it is about family or otherwise important.
What medical conditions seem more common now than when you were growing up?



).

) but as you say I don't need this person's approval and the fact is she was wrong . 
