Dear Miss Manners: Dieting in public is a serious etiquette problem in a society that has made saints of women who wear a size 2. It is rude and offensive for a person to attend a joyous food-related outing and have one person, the chronic dieter, spoil the trip by ordering "a small salad."

Public dieting casts a pall of misery over any such occasion. The argument that the outing is about the fellowship is only partially true — the fellowship is enjoying a good meal together. The occasion IS about the food, and no matter how one tries, it is as impossible not to notice how little that emaciated person is eating any more than one could not help but notice an oozing sore on her hand.

Holiday dinners and meals out with friends are a time, if not to eat heartily, to at least to eat well — even if one chooses grilled instead of fried chicken or replaces the dressing with vegetables at Thanksgiving. If one must diet in public, it should be done with absolute discretion and must involve a variety of tasty foods chosen from what has been provided. If the dieter wants a diet soda, she should ask for it quietly, as though requesting something with which to take medication and have it poured into a glass to ensure that the nature of the drink is not obvious.

If a person is on a super-restricted diet that requires she eat abnormally, she needs to stay home instead of making everyone miserable. Perhaps she can join the group later for a concert or movie if she is not too weak to stay out past 8 p.m.

Gentle Reader: That part about how you try not to notice what other people are eating — Miss Manners suggests that you try harder. A lot harder.

Monitoring what other people eat is a good way to ruin a holiday or gathering of friends, whether it is dieters voicing disapproval of hearty eaters or the more rare reaction that you have.

But after you stated your desire to ostracize everyone with medical or religious food restrictions, Miss Manners banned you from any discussion about what constitutes fellowship.

Dear Miss Manners: Two of my close friends, my roommate and my ex-boyfriend, quiz me about things I feel should remain private, such as my sex life and intimate details of my family's finances. I try to be discreet or vague, or flatly tell them that it's not their business, but they protest that we know each other well enough that I can — and should — tell them everything.

They know I'm not being entirely forthcoming, and my ex often asserts that I'm a liar. They will not be deterred and I'm tired of fending off inappropriate questions.

Gentle Reader: Then don't. By now, you need only say, "You know I'm not going to discuss that," not adding that you would have to be an idiot to confide your sex life to your ex.

Miss Manners is well aware that the reply is likely to be one of those accusations you cite, but then you can say gently, "and you know perfectly well that I'm not going to discuss that, either."

Readers may write to Miss Manners at [email protected], or via postal mail at United Media, 200 Madison Ave., 4th Floor, New York, NY 10016 or (in black or blue-black ink on white writing paper) to Miss Manners, in care of this newspaper. Miss Manners' newest book is "No Vulgar Hotel: The Desire and Pursuit of Venice," written under her real name, Judith Martin. © Judith Martin. Dist. by United Feature Syndicate Inc.