I am sorry you had to deal with such. Few understand it seems what it really means to teach someone or take them on as an apprentice. There is a distinct difference from offering advice or even helping to offer guidance in matters from the full relationship of teaching someone in depth. Most tend to crack under even the advice and guidance stages in my experience and that can be frustrating enough especially when they make a mess of things after going insane. While I have not done in-depth teaching as I am rather old school master apprentice beliefs in relation to that I can well imagine it.
It really shows that real guidance and teaching cannot be given en-mass no matter how ‘good’ someone is at it and such displays are usually simply for the arrogance of the individual running his mouth or worse yet feed for their delusions that unfortunately drag and trap others some that might be real potentials down the same maggot infested rabbit hole. It is something unique to each individual and takes time and a deep connection. While cursory advice and guidance can be derived from articles, books, etc, and better be given on an individual level even that takes time to truly be effective and is only as valuable as the source and the one taking it in.
To extend that level of trust and time and effort only to have the one you are bothering with be a brick wall. Well it is not fun and often feels like a total waste past what you learn in discretion among those you choose to advice and guide on a more in depth level.
Also I believe the saying is “Fuck the dog if you wanna, better looking than your cousin.” But maybe that is a local saying of this town.