*hugs* I understand that. You're marvelously competent at a wide range of things -- good person to have around during the collapse of civilization -- but imposter syndrome is a bastard.

Don't know if it helps, but the person delivering unhelpful vague critique might be bad at hard conversations and have thought that vagueness was protective. And most people react pretty well to an honest "I've heard someone is having some sort of issue with me, and I'd really like to know what so that I can work on fixing it."

Of course, some other people are assholes, so *shrug emoji*