DEAR MISS MANNERS: At a celebration and everyone was having a happy time ... lots of smiles and good humor. I was in a lively conversation with another guest, and we were laughing over some quip or observation when she suddenly asked, with no warning, "How old are you?"

It was so unexpected that I think I probably just gave her a startled look and gasped, "What?" (or perhaps even "Huh?"). So the lady explained with a generous smile, "You seem so YOUNG."

Ouch! What a left-handed compliment! What she was actually implying was, "You look so OLD!"

What would be the best response to this exchange? I was too stunned to come up with an appropriate response. When I'm having fun, I assume that I look like "everyone else" at the gathering.

Should I have smiled wanly and said, "Thank you"? Or, a better idea, should I have returned the compliment by telling her, "And you seem so young too!"

In my own case, I do have an ideal response: "I was born on a date that will live in infamy," and leave it to the questioner to figure it out. I just want to be prepared if/when this happens again.

What would Miss Manners suggest? This would never happen to you, but it did to me, and it left me feeling disheartened.

GENTLE READER: It could easily happen to Miss Manners, as many people casually break the rule against asking the age of anyone past childhood. But there is no chance that it would make her feel disheartened. She knows her age and is neither flattered nor insulted to have people recognize or mistake it.

You are a victim of the silly, harmful and futile modern convention that it is embarrassing to grow old. Although your interlocutor violated the rule that age should not therefore be mentioned, her retreat shows that she was aware of it. That is why she reverted to the fiction of clumsily claiming that she was referring to your youthfulness.

Mind you, you need not tell your age. Your answer is acceptable, but you could also reply that you do not tell. (The standard coy reply is Oscar Wilde's "A woman who would tell one that would tell one anything.") Miss Manners is urging you only to not allow such remarks to upset you.

DEAR MISS MANNERS: All my friends were invited to a party but me. How do I respond to the host or if my friends should ask why I wasn't there?

GENTLE READER: Because she spends a ridiculous amount of her time urging people to answer invitations, Miss Manners is delighted to tell you that you do not need to respond to a host who did not invite you.

If a host asks, it means that there was the intention to invite you, and something went wrong, presumably in the delivery. Your response should be the same as to anyone else inquiring: "I wasn't asked," said cheerfully enough to show that there are no hard feelings.

(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: Is it acceptable to wave at someone once you have made awkward eye contact? Or should you just wink and hit 'em with a terrible pickup line? Any help you can give me would be much appreciated, as this happens to me quite often. I have tried both options, and my counselor seems to think the pickup line is what gets them.

Also, what is your opinion on a guy's height? Because I have been told that once you get over 6 feet tall, you get more ladies, yet that is not occurring to me.

GENTLE READER: Huh? Presuming the best, Miss Manners hopes that you are simply seeking acceptable ways to start a dialogue with strangers of the opposite sex in order to get to know them better.

First, she strongly encourages you (and your "counselor") to stop thinking of ladies as something to "get."

Actually, there is no "second." Try thinking of women as actual people who enjoy real and interesting conversation -- not weird hand gestures, offensive or half-baked lines, or exclusive physical fetishes. Approach them as such and you should be fine -- or will learn otherwise quickly.

Miss Manners assures you that she has no opinion on height other than its convenience for out-of-reach items and further wonders how you plan on adjusting yours now that it has occurred to you.

DEAR MISS MANNERS: We are staying in a vacation rental for a month, and we had guests fly in to join us for four nights. Their flight home was scheduled to leave at 5 p.m., so we needed to drive them to the airport at 2 p.m., which gave us time to enjoy the rest of the day on our own.

Their flight was delayed by 2 1/2 hours. We learned about this delay a good hour before we needed to leave for the airport. How should they have handled this delay?

Could they say they are delayed and expect us to put the rest of our day on hold, waiting to take them to the airport?

Could they have not told us about the delay and let us take them to the airport, allowing us to enjoy the rest of our day?

GENTLE READER: Or your guests could admit to being delayed and offer to get themselves to the airport. You would still be left with a decision to make -- delay your plans or take them up on their offer -- but your guests would not have had to lie in order to be gracious.

If this plan is not forthcoming, you also have the option to say, "I am so sorry, but we made plans for the rest of the day. Could we help arrange for some other means of transportation?"

But perhaps the real problem here is with the guests themselves. Yours have seemingly done nothing wrong. But the fact that the enjoyment of your day seems to be predicated on whether or not you have to spend another partial afternoon with them is sad. Miss Manners suggests that in the future, you vacation with friends who are a bit more entertaining. Two and a half hours' worth, to be exact.

(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 today's age of constant contact with our ever-present phones, what's the appropriate response when a friend with an alternative schedule (for instance, working in another time zone) contacts me during work hours on my personal cell?

I feel awkward ignoring their calls, but also feel perturbed that they do not appreciate that I work standard business hours.

I received a mid-afternoon call on a Monday from a friend who informed me that now was a good time for him to return my Sunday call, but unfortunately, I was working and wasn't available for a long chat. I felt rude but confused as to how I should have handled it.

I am salaried and could take the call and leave work later, but also feel that it is unprofessional and keeps me "on call" around others' schedules. I would appreciate your advice on texts of a similar nature: It seems not responding immediately to texts is now considered rude!

GENTLE READER: Because technology has made it so that everyone is immediately reachable does not, Miss Manners assures you, mean that humans have to follow suit.

Since it is so commonplace for people to turn off their ringers, it is likely that no one pays attention to the time that they are calling anymore. But that does not mean you have to answer it.

If it makes you feel better to blame it on technology, then do it fully. Leave an outgoing voicemail message (or text equivalent) that states your business hours and when you will be able to reasonably return calls. You may find that your devices end up talking to one another for a while, but at least your job security -- and general sanity level -- will be safe.

DEAR MISS MANNERS: My daughter just got married in a small ceremony, and a group of about 20 friends and family went to dinner after, which I had arranged. The groom's parents offered to pay half the bill, which wasn't a problem -- but their credit card was declined.

As I was the one the wait staff was dealing with, I simply paid the entire bill and handed the declined card back, while saying, "It's all settled."

Was I wrong to not give them a chance to pay a different way? I assume they'll figure out eventually that they weren't charged, and if they insist on paying me back, they'll figure out a way to do it. But my main concern was avoiding embarrassing them in that celebratory moment.

GENTLE READER: Which was tactful. Miss Manners assures you that it also would not have been remiss to have taken one of the other parents discreetly aside to explain the situation. Cards may be declined for reasons other than fraud.

But if you were in a position to be generous without making a show of it -- or insisting on immediate payback -- it bodes well for the future of the relationship. Or -- if it becomes a habit -- its complete and utter demise.

(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.)