Every now and then, we all wonder about whether we’ve behaved appropriately in a given social situation. Did we say something rude? Was seven bacon-wrapped shrimp more than our fair share?

But it’s hard to imagine most women acting in a way that would necessitate an email like the one that was sent to 29-year-old Heidi Withers from her future husband’s stepmother. In it, Carolyn Bourne, 60, details the ways in which Withers offended her fragile sensibilities on a recent family trip.

The email wound up on the internet after Withers forwarded it to some friends, who forwarded it to their friends, and so on, until it made it into the Telegraph and Daily Mail.

Here are some examples of what Bourne calls Withers’ “lack of manners”:

“When you are a guest in another’s house, you do not declare what you will and will not eat – unless you are positively allergic to something.

”You do not remark that you do not have enough food. You do not start before everyone else.

”You do not take additional helpings without being invited to by your host.

“When a guest in another’s house, you do not lie in bed until late morning in households that rise early. You fall in line with house norms.

You should never ever insult the family you are about to join at any time and most definitely not in public. I gather you passed this off as a joke but the reaction in the pub was one of shock, not laughter.

“You regularly draw attention to yourself. Perhaps you should ask yourself why. No one gets married in a castle unless they own it. It is brash, celebrity style behaviour.

“If your parents are unable to contribute very much towards the cost of your wedding, it would be most ladylike and gracious to lower your sights and have a modest wedding as befits both your incomes.

“One could be accused of thinking that Heidi Withers must be patting herself on the back for having caught a most eligible young man. I pity Freddie.”

So, wow. Someone’s wedding just got a little more complicated.