DEAR MISS MANNERS: A rather despicable married friend has been estranged from her husband for years, yet they maintain a home together. She has had several love interests in the past few years. I suspect I've been used as her "beard" for some of her escapades.

I don't really wish for her to be at our wedding, but nonetheless must invite her. I despise her husband and he feels the same of me. Is it permissible to simply invite her? I know her husband will not attend, and I fear if I address the invitation to Mr. and Mrs. it will encourage her to bring a guest.

If I've painted a portrait of a woman who lives beyond the conventions of etiquette, I have painted well, so please don't say she'll have sense enough not bring a guest other than her husband. She will not, and I can't abide the thought of a married woman bringing a date to our wedding.

GENTLE READER: Are you seriously sticking Miss Manners with the premise that this person is your friend and you must invite her?

All right, but then she also accepts your premise that your friend is beyond the conventions of etiquette. In that case, if she wants to bring a guest, she will bring one, regardless of what you put on the invitation.

So you might as well do the correct thing and invite the couple as a couple. If a couple maintains a home together, etiquette does not investigate whether they are getting along.

DEAR MISS MANNERS: When my husband and I are invited to the home of new friends for a meal, the first thing that happens is that we're offered a tour of the hosts' house, from top to bottom. Obviously we are expected to admire their views, their choice of furnishings, their craft projects and so on. What do you think of this practice?

GENTLE READER: That such people should offer their houses to be on a local house tour, such as are given as charity fundraisers in the spring. If accepted for such use, the owners will be able to garner widespread admiration and/or criticism. If not accepted, Miss Manners hopes that they may come to realize that gaping at their possessions is not all that entertaining.

We are supposed to believe that the reason for socializing is to enjoy the company of others, not to admire -- really meaning to appraise -- their possessions.

DEAR MISS MANNERS: I would like to know the proper etiquette for giving mother's rings. More specifically, is it proper to place the birthstone of a son who committed suicide in the ring? Wouldn't it be rude not to include it? Also, it is customary to present the ring as a gift for Mother's Day, but is that etched in stone or may it be given at any time?

I am desperate for the answer; the trials and tribulations that our family have endured this past year have produced a perfect time to honor my mother-in-law for all her strength and enthusiasm.

GENTLE READER: There is no specific rule about such rings, but there is one about recognizing a mother's children. Miss Manners assures you that your mother-in-law has not forgotten her son who committed suicide, and however painful her memories, it would be more painful to think that you have forgotten him, or worse, that you believe that she has.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: My husband's niece was engaged to be married in the summer, but the wedding was moved up because she and her fiance decided they couldn't wait. Their ages are 19 and 18, respectively.

She announced on her Facebook page that they were getting married that day. This was the only announcement; no formal communication was sent out, even to family members.

My husband insists that a generic announcement to the entire Facebook world does not warrant a wedding gift, and I am inclined to agree with him. The rest of his family has been sending gifts. We don't feel we should be required to add to the general decline in manners, but we're also afraid that making conditional terms for gift-giving may be a breach of etiquette in itself.

How does one handle the unfortunate new etiquette of the Facebook age?

GENTLE READER: And how does Miss Manners handle the unfortunate misconceptions about the etiquette of giving wedding presents?

There is no such thing as an invoice for a wedding present. Neither a wedding invitation nor a formal announcement constitutes that. You give a wedding present because you want to indicate symbolically that you care about the couple.

Yes, there is a catch. That is that you should not be attending a wedding if you do not care about the couple (either truly, or because they are relatives and you are supposed to care), and therefore wedding guests give wedding presents. If you decline the invitation, or if you are not invited but receive an announcement, all that is required is that you send the couple good wishes.

So even if you had received a formal announcement of this marriage, you might have skipped the present. But remember that word "required." That means the decent minimum, which many people rudely skip, because they consider that an invitation is an invoice, but an announcement can be entirely ignored.

Your quibble is that not only were you not invited to a wedding, but you didn't even get a formal announcement. But look at the circumstances. An elopement is the least formal wedding, which is fine, and the couple chose the least formal way of letting people know about it.

So -- what is required of you? Nothing, if you want to pretend that you didn't see their posting, until you are told directly. However, an expression of good wishes is necessary if you admit that you do know of the marriage. Adding a present over this minimum would show that you care. Or that you want, for the family's sake, to seem to care.

DEAR MISS MANNERS: Are the rules for teachers different? As a parent, I have sent in countless gifts to the teachers, with the giver listed as one of my children. In about half the cases, the teacher sends a thank-you to the child.

How I relish watching my children receive those thank-yous! It reinforces the lessons of good manners and the art of writing thank-yous. My children love receiving those simple notes. But I am deeply disappointed with those teachers who do not write thank-yous. Am I expecting too much?

GENTLE READER: Well, you are expecting teachers to set good examples and to understand, as you do, how much this means to children. As overworked and underpaid as teachers are, Miss Manners would expect them to feel the effort was worthwhile.

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: My daughter-in-law is expecting in July. However, she thinks she should celebrate Mother's Day now. I am a bit old-fashioned; I do not recall celebrating Mother's Day if you are only pregnant.

GENTLE READER: As the idea of Mother's Day is for mothers to be shown appreciation by their children, your daughter-in-law has a problem. Even though she is devoting herself to the nourishment and well-being of this child, she is unlikely to receive chocolates, roses or even a card from that source.

Miss Manners recognizes that two ungracious trends have fueled your daughter-in-law's wish. The first is that people now feel emboldened to declare that others must honor them. Typically, this is expressed in self-generated adult birthday parties and showers. Rather than waiting for others to be moved to organize such an event, the would-be guest of honor initiates it, sets the terms and expects the guests to pay the bills.

The second is the enlargement of Mother's Day beyond that of filial gratitude. That fathers should participate makes sense, especially when the children are young enough to require some guidance, and because he is an indirect beneficiary. But expectations have spread ridiculously. Miss Manners has heard from mothers who expect even their own mothers to pay them honor, and, in contrast, from childless ladies who are upset that acquaintances and strangers wish them a happy Mother's Day.

That your daughter-in-law associates the holiday with her impending motherhood does not bother Miss Manners. That she has seen fit to announce that she expects to be celebrated by others does. Why isn't she busy making Father's Day plans, instead?

DEAR MISS MANNERS: Should I get a Mother's Day gift for my girlfriend? She's not my child's mother.

GENTLE READER: Is she yours?

DEAR MISS MANNERS: I have a successful adult son who has been married for almost 10 years and has a young child, no longer a baby. We have entertained this family many times, especially for holidays and family get-togethers.

I feel that this young couple should reciprocate at least occasionally. Never once have they invited us for dinner or to their apartment.

Do I have a reason to feel nonplussed? I certainly invited my in-laws very regularly to my house, even as newly marrieds. My husband won't let me say a word.

GENTLE READER: He probably suspects that the words you want to say are, "We have entertained ... never once have you ... I certainly invited ..." and so on.

But the people you refer to as "this family" and "this young couple" are your own son and daughter-in-law. You could express interest, rather than bitterness. The words Miss Manners would suggest, to which your husband would probably not object, are: "Could we do this at your place sometime? We love having you here, but it would be fun to spend time in your home. I would so enjoy that."

(Please send your questions to Miss Manners at her website, www.missmanners.com; to her email, dearmissmanners@gmail.com; or through postal mail to Miss Manners, Universal Uclick, 1130 Walnut St., Kansas City, MO 64106.)