DEAR MISS MANNERS: A few years ago, a longtime friend sent me a private message through social media that just said, "Don had a massive heart attack and passed away."

I instantly thought it was a mutual friend I had been close with for over 20 years, but whom I'd been out of touch with for a couple years due to my move to another country. I was so upset and in tears at the news, I had to leave work early that day.

When I got home, I frantically reached out to other mutual friends only to find out that "my" Don was alive and well. Come to find out, the friend who sent me the message was referring to her ex-husband, whom she had been divorced from for many years and who rarely came up in conversation.

Still recovering from my grief and shock, I posted that it is VERY important to clarify who you are referring to when sharing bad news. I did not mention my friend, but she immediately "unfriended" me with a comment that I had "called her out" and embarrassed her, that she was struggling with her own grief and that I was selfish to post something like this "for attention."

I emailed her numerous times and apologized if I had offended her. It has been almost three years, and I still reach out to her occasionally with an olive branch by email or phone. But there is no response; it seems she has decided my offense was unforgivable, and I am now grieving the end of a 20-year friendship over a social media post.

I don't think I did anything horrible, given the circumstances, but what are your thoughts?

GENTLE READER: Your original post was a public service, Miss Manners understands. She also understands why your friend did not see it that way. Nor, come to think of it, did you, since you felt called upon to make years' worth of apologies.

The real question is: Was it so bad that you cannot be forgiven? Miss Manners is inclined to agree that your friend is overreacting -- assuming, of course, that the apology was for the post and not merely for your friend being offended by it.

DEAR MISS MANNERS: A dear friend has the odd habit of bursting into not-so-quiet song while browsing through stores, sitting in restaurants or riding in the car. Her voice is OK, but it's both awkward and distracting, especially when one simply wants to listen to ambient music in her presence without unsolicited harmonies. I don't want to offend her, but find myself increasingly annoyed.

GENTLE READER: The best thing about singing is that it is not meant to be interrupted. You might pretend your friend said something you could not hear, and ask her to repeat it. Miss Manners trusts that the annoyance of having to stop to clear up your confusion will dampen her enthusiasm for another verse.

(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, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: In social settings, is it OK to finish a conversation and walk away when doing so leaves the other person awkwardly alone?

I was chatting with someone I did not know at a party. After about 20 minutes of pleasant conversation, I used a pause to say I was going to refresh my drink and asked if the man would like one himself. He said no, and I walked away and joined friends in another room. He was left sitting alone, and I felt a bit guilty.

I know I'm not obligated to sit with him until someone else joins us, which may not happen, but is there a better way to leave?

GENTLE READER: The only people who never have such awkward moments -- being stuck talking to the same person or being left adrift -- are people who refuse to attend these types of parties. And Miss Manners cannot say that she blames them.

Had another guest been on the loose in the vicinity, it would have been graceful for you to nab a substitute as you left. But such is not always the case, and your excuse, which implied that the gentleman could have accompanied you to the bar, or that you would have been willing to come back to him with a drink had he wanted one, was polite.

Such parties are hazardous, and the hosts should be on the lookout to draw people together. But there is only so much guests can do to rescue one another.

DEAR MISS MANNERS: I have a friend who asks me from time to time to go shopping with her. Neither of us has a car, so we use public transit, and always eat out where we shop.

The trouble is, she finds a problem with everything -- from the driver of the bus to whatever she has ordered at the restaurant. At a restaurant, for example, she will order more biscuits or a to-go drink AFTER the bill has been presented. She is very loud and repetitive about making her case known. She will keep repeating herself over the person in charge, confusing them and blaming them.

I have told her that her complaints would be more effective if she did not scream repeatedly at the staff, and also that it is wrong to order food after the bill arrives. But she says they expect this, as she has waitress experience -- which amounts to about six months over the course of her 58 years. It's left me not wanting to go shopping with her at all.

Other than this behavior, I love her conversation and company. Any ideas on how to deal with her?

GENTLE READER: Well, not by shopping or eating out, as Miss Manners trusts that you have learned.

Why don't the two of you go fishing together? Or hiking in the mountains? Or skydiving? Then you could enjoy each other's conversation without causing collateral damage.

(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, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)

DEAR MISS MANNERS: One's bank account, knowledge of formal social rules and ability to follow table etiquette are not necessarily synonymous with true graciousness, consideration and courtesy. In fact, they may be covering up one's insincerity and disdain for others. I find it unfair that the well-dressed and seemingly more refined are often credited with being more "appropriate" in society than those who are unpretentious and casual.

The backstory is that when my sister and I were children, one aunt would take us into the city for dinner and a play, introducing us to the more refined things in life. It was very enjoyable at the time. We considered her lessons on how to present oneself in a dignified manner and follow respectable social mores invaluable. She was quick to point out social gaffes and inappropriate dress and demeanor, thus teaching us how to perform in social situations.

Some years later, after we were grown -- and after having slowly grown apart from this aunt, as well as from another aunt and cousin -- my sister decided to invite them over to her home for dinner. It was a small gathering. They arrived two hours early, taking my sister off guard, but she said nothing.

During the course of small talk, while waiting for the meal to finish cooking, they commented on a liqueur bottle perched on a shelf. My sister enthusiastically offered them a sip and poured the servings into appropriate liqueur glasses. While sipping the liqueur, one aunt, frowning seriously, commented that this beverage really should not have been offered until AFTER dinner. She whispered this to our cousin and other aunt, but I overheard her quite clearly.

Later, the subject of a famous family from the Italian Renaissance came up. I unknowingly mispronounced the surname of this family, and was sternly corrected by one aunt.

When dinner was being served, my cousin mentioned that she was quite scared to drive through our town as she thought she was being "followed by gang members," and that some people she knows (not her, mind you) thought that where we live is a "ghetto." Our cousin also commented on how "comfy and lived-in" the home is, and how charming she found the mismatched furniture.

Who is more guilty of a rude, offensive social gaffe? The one serving guests an after-dinner drink before dinner, or the ones arriving two hours early, correcting another guest's grammar and insulting the host's home and neighborhood?

GENTLE READER: It would be difficult for anyone with normal powers of observation to believe that there is a link between having money and behaving well. So let's not start class warfare here.

Besides, they are your own relatives. And while they are no longer exemplars of good manners, they are used to thinking of you as a child in need of instruction. If you cannot bring yourself to find this amusing, Miss Manners suggests gently reminding them that you are now grown up and responsible for your own behavior.

(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, Andrews McMeel Syndication, 1130 Walnut St., Kansas City, MO 64106.)