For email, the old postcard rule applies. Nobody else is supposed to read your postcards, but you'd be a fool if you wrote anything private on one.
Judith MartinIt is a widespread and firm belief among guests that their departure is always a matter of distress to their hosts, and that in order to indicate that they have been pleasantly entertained, they must demonstrate an extreme unwillingness to allow the entertainment to conclude. This is not necessarily true.
Judith MartinWhen you consider how epidemic boredom is in our time, you have to concede that entertaining is a healing art.
Judith MartinThe etiquette question that troubles so many fastidious people New Year's Day is: How am I ever going to face those people again?
Judith Martin