DEAR MISS MANNERS: I am a lifelong nonsmoker and naturally do not permit anyone to light up in my home or in my car. No exceptions. But when I’m a passenger in a vehicle driven by a friend who smokes, they will inevitably light up without asking if it’s OK.

They'll crack their window and blow the smoke out through the crack. Even so, the wisp of smoke from the still-burning cigarette quickly begins to fill the entire vehicle. It causes me to cough and rub my burning eyes. The friend will usually notice, sometimes offering a “sorry” and will perhaps extinguish their cigarette a minute sooner.

What is my best option, other than not getting in the car at all with a driver who smokes? Would it be rude for me to politely ask them to refrain from smoking until we reach our destination?

Yes, it’s their vehicle, their rules. But the health of my lungs should also matter.

GENTLE READER: In a more general form, yours is one of the principal etiquette questions of our day. But that question is often, to Miss Manners’ thinking, misstated.

Anyone with a serious medical condition understandably asks, "Whose need is greater?" And, in extreme situations, basic decency demands aiding those in need.

For more everyday situations, the proper question is, "How much can a guest reasonably impose upon a host?" The answer will depend on the closeness of the friendship and the extent, and frequency, of the imposition.

Used wisely, with a friend (not a mere acquaintance), there is an alternative to always declining a ride: You can decline with the explanation that even a little smoke bothers you and you do not want to impose. The driver can then decide whether to issue a second invitation, knowing that doing so is agreeing to more stringent conditions.

DEAR MISS MANNERS: My neighbor, with whom I have friendly chats, sent a group text to several women, including me, inviting us all to meet for dinner at a local restaurant, followed by a yoga class. I responded that I would love to come to dinner.

When I showed up at the restaurant, she looked at me and said, “What are you doing here?” I was shocked and didn’t know how to respond and blurted out that she had invited me.

I still feel awkward and don’t know how I should have responded in that moment. Now I just feel uncomfortable around her. What should I have done?

GENTLE READER: Your neighbor’s statement is too hurtful to be excused, so you are going to have to reinvent it out of existence.

Miss Manners is not suggesting you pretend your hearing aid malfunctioned -- that might actually elicit a repetition. Instead, treat it as a joke.

Before you object that this is disingenuous, consider how grateful everyone present will be to be given this graceful way out -- including your neighbor, though her gratitude may require time. If that process is going to be measured in units larger than minutes or hours, then you might wish to space out your future interactions with her accordingly.

(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: I am currently staying with a family friend and her husband for a few days while visiting my hometown. The husband clearly isn’t happy with me staying here, so I have not interacted with him much.

On my second day here, the husband asked for a divorce. Now I can hear them fighting, and the tension is insane.

How do I interact with him further? Is it rude if I just avoid him? Currently, our conversations are barely existent.

GENTLE READER: Currently? Your hosts are fighting to the point of divorce, and you are sticking around, listening? And your only question is how to deal with an ungracious host?

A guest must also be gracious, even under extraordinary circumstances. The rule that applies here is the one about happening upon accidents: If you can help, jump in and do so. If not, don’t gawk -- move on.

Miss Manners wonders why you did not leave for your own sake when you noticed that the host was unhappy with your being there, for whatever reason. Surely the awkwardness and inconvenience you would have experienced would have been better than being an unwelcome guest.

What you could have said to him and his wife on your way out was, “I wish you both well.”

DEAR MISS MANNERS: I live in a five-story condominium building that has a lot of retired people in it. I have been at the same job for 20-plus years, so I have a lot of vacation days. I don’t often take a week or two off at a time -- more often just a day off here and there.

My neighbors can’t get their heads around this. I have been repeatedly asked, “Oh, do you work every day? Do you have Fridays off? Why aren’t you at work?” It really burns me, as they’re implying I’m doing something wrong and that my schedule is their business.

Most of the old-timers have left since I moved here, but there are still a few older busybodies around. They seem to suffer from “groupthink” and a tendency to interfere with others.

Also, they are so oblivious. It goes right over their heads that they might be bothering people with questions like this. Goodness, if I did have a sickness or some kind of personal reason for being home, I wouldn’t necessarily want them to know that!

Sometimes I even go down the stairwell and take different routes to avoid running into these people.

GENTLE READER: Have these people not heard about remote work?

Not that Miss Manners believes that hearing that explanation -- or any other -- would discourage a determined busybody. Sadly, they are just after a bit of conversation.

Which does not mean that you need provide it. Ignore the questions, call out a cheery greeting -- “Hi, Mrs. Erskine!” “Nice day, Mr. Lumpkin!” -- and keep moving.

(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: My dog is a great conversation starter. Strangers who stop to admire him will often share a story or two about their own pets, or their own memories of dogs they’ve known.

As much as I enjoy this, I’ve noticed that these strangers will often -- with no prompting from me and with no obvious conversational cues leading toward this topic -- tell me about how their pets or pets belonging to their friends died. These stories are often detailed accounts of how they, or someone close to them, caused the death of their beloved animals, usually by accident, leading to years of emotional fallout and sad memories.

I understand that losing a pet is difficult. I understand that it’s 10 times worse when that pet is killed on accident by someone who loves them, and I understand that people who have lost pets in such a way might find solace in discussing their grief with a friend.

But I’m not their friend. Most of the time, I don’t even know this person’s first name. They will, without exaggerating, stop me to chat about my dog, share a story about a dog they’ve known, and then hit me with “Yeah, my daughter ran him over with her truck. None of us have ever been the same.” Or something to that effect.

I find these stories distressing, even more so because they come without warning from people I don’t know. Can you suggest a polite way to interrupt these stories?

If there isn’t a polite way to prevent this from happening, is there a gracious way to admonish them for luring me into a conversation about their cute dog, only to ruin my day with a graphic account of the cute dog’s tragic demise?

GENTLE READER: Admonishing them -- no. But you can stop them.

At the first sign of a disaster story, Miss Manners suggests holding up your hand and saying, “Wait -- Fido (or Achilles or Sweetums, whatever your dog's name) finds this kind of story upsetting. I don’t want him to have nightmares. Please excuse us.”

Or you could try training him to respond to a signal by pulling you away, as you flash an apologetic look to the stranger.

DEAR MISS MANNERS: I often vacation at the beach and pick up several postcards with the full intent of sending them, but rarely get around to it. Is it bad etiquette to send them from home?

Someone once told me you should only mail postcards if you can manage to do so from the location you are visiting, but I feel like it’s nice to tell someone you are thinking of them, no matter where you are. Is it tacky that they won’t be postmarked by the location?

GENTLE READER: Postcards? You prefer pictures of places and handwritten greetings to bombarding your friends with selfies?

That is so nice that Miss Manners does not want to quibble. Well, she supposes you might change the tense in your messages, depending on the timing: “I was in Whaler’s Beach, thinking of you.”

(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.)