But that rule doesn't always extend to holiday cards. There, along with the smiling pictures and upbeat updates, you also might learn about the year's marital debacles, bad diagnoses or heartbreaking fertility problems.
Refreshing honesty or too much information?
The tell-all holiday card or letter has been around for a few years now, said Diane Gottsman, a Texas-based etiquette expert. She believes that a holiday card is supposed to be a warm greeting; if you want to update people on the harsh realities of your life, have that conversation in person.
"The holiday card should warm hearts, with some small note," said Gottsman. "Droning on about your divorce and how your ex-husband did you wrong? The card is not the venue for this kind of news."
LisaMarie Luccioni, a professor of communications at the University of Cincinnati, said people have grown skeptical, however, of the crafted, idealized versions of life they see on Facebook. The holiday card can serve as a reality check, she said.
"I actually appreciate the candour and honesty of people in these types of cards," said Luccioni. "I'm a professor of 25 years and I appreciate when a student gives me honesty."
Despite the availability of electronic greeting cards, many people still send paper holiday cards, sometimes including page-long "newsletters" summarizing the year. The greeting card industry says Americans buy 6.5 billion cards each year, for annual sales of between $7 billion and $8 billion. Christmas is by far the most popular seasonal event for cards, according to the Greeting Card Association.
For many people, it seems, paper cards or newsletters connect on a more personal level than an e-card, said Margaret Page, an etiquette coach in Vancouver, British Columbia.
She thinks that senders of holiday cards might say too much because they're not connecting closely enough the rest of the year.
"Social media is not really being connected," Page said. "People are desperate to make real connections, and are using Christmas cards, birthday cards, to share information with others that they wouldn't have a decade ago . or even five years ago."
A lawyer in Boise, Idaho, who asked not to be named, decided to share the reasons behind her divorce in a Christmas letter two years ago.
"I just thought, you know, I'm going to be honest with our friends and family, and just put it out there," she said. "I also didn't want to repeat the story 100 times, and that's kind of where I was at."
She was uncomfortable putting information on social media that could be seen by people outside her circle of friends.
The format of a letter can serve as a signal that big news might be coming. But a card should stay light, said Gottsman, who thinks heavy use of social media reinforces the idea that it's OK to deliver all kinds of news — good, bad, personal, gossipy — in a holiday greeting.
"The right venue to deliver bad news is in person, or over the telephone. Or if you can, send an informative letter," she said.
"And you know, we do care about these peoples' lives, generally. But sometimes we don't even know them very well, and we want to get to know them in the right way."
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