Q. I have learned through a third party that a friend, who is feeling particularly insecure these days, has not been invited to the forthcoming book launch of one of our long-standing mutual friends. I don’t want to portray him as some kind of victim, but is there a way I can tactfully find out if, best-case scenario, his failure to receive an e-invitation was, as it so often is, a mistake by the publishers’ intern? Or if, worst-case scenario, he has been ruthlessly excluded on financial grounds for no longer being an ‘influencer’? This author is paying for his launch himself...