The first time I can think of, I completely misjudged the situation. I was told that the story wasn't autobiographical and like a dimwit I took the statement at face value. Oh dear. I can't remember the details, but in the text the narrator appeared to loathe her parents which I commented on. It did not go down well. I stuck to my point; what was written on the page was loathing, and if the writer wanted it to be loving, then the text needed changing. This didn't go down well either.
Actually, most of the time when things haven't gone well, it's been when there has been a strong autobiographical element. The time I asked, 'Your narrator is coming across as rather shallow and immature - is that what you intended?' was another low point as the comment was taken personally (in a rather shallow and immature way, I suppose).
So I know that I'm guilty of putting people off. I'm sorry if that's you. My intentions were to be helpful and useful, and I think the advice I've offered has been good. But then, I would say that, wouldn't I?