DEAR ABBY: You have mentioned in the past that you have a booklet on writing letters, including thank-you notes. Where do I send for it? I'll need four because my grandkids are lacking in that area.

It's truly a shame that younger generations haven't been taught about the importance of such notes. A simple "thank you" can not only open doors of opportunity both socially and in employment, but also help grandparents feel appreciated after their heartfelt gift-giving. -- NANCY IN NEVADA

DEAR NANCY: If there is one subject that crops up repeatedly in my mail, it's thank-you notes -- or rather, the lack of them. I print letters about it because of the number of complaints I receive. When a gift or a check isn't acknowledged, the (unwritten) message it sends is that the item wasn't appreciated, which is insulting and hurtful.

Chief among the reasons that thank-you notes are unwritten is that many people don't know what to say. They think the message has to be long and flowery when, in fact, keeping it short and to the point is more effective. My booklet, "How to Write Letters for All Occasions," contains samples of thank-you letters for birthday gifts, shower gifts and wedding gifts, as well as those that arrive around holiday time. It also includes letters of congratulations and ones regarding difficult subjects, such as the loss of a parent, a spouse or a child. It can be ordered by sending your name, mailing address, plus check or money order for $7 (U.S. funds) to Dear Abby Letters Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Shipping and handling are included in the price.) With the holiday season approaching, this is the perfect time to reply with a handwritten letter, note or well-written email.

Because the composition of letters is not always effectively taught in the schools, my booklet can serve as a helpful tutorial, one that is valuable for parents as a way to teach their children to write using proper etiquette.

DEAR ABBY: I have been dating this guy for a year and a half and he's not into making love. He's happy if we only do it once a month and, when he does give in, he will only do the same old position. I, on the other hand, enjoy sex.

My ex (we have been apart eight years) is now in a sexless marriage. We started hooking up six months ago -- just for sex -- and it is awesome. Part of me feels guilty because I'm against cheating, but I need sex. What should I do? -- CHEATING IN THE NORTH

DEAR CHEATING: Because the man you have been dating for a year and a half is a sexual mismatch, you need to end the romance. It would be kinder than continuing to cheat on him.

Your married ex may seem like an oasis in the sexual desert right now, but don't waste more time on him. He isn't your future; he's your past for good reason, I'm sure -- so keep him there.

DEAR ABBY: I am a lesbian. My girlfriend and I have been dating for six months. We have an awesome relationship and are very happy and open with each other.

I know she has dated guys in the past -- so have I -- so I'm not worried about that nonsense at all. But I recently found something of hers that surprised me. It was a container of pregnancy tests, and one was missing with a Plan B pill alongside of it. I am not mad about it because I know stuff happens, but I would rather that it not happen in our apartment.

I'm tempted to bring it up, but I would honestly rather not discuss it at all. I just don't want anything happening in the apartment. Would it be weird if I just threw the stuff out without telling her, or should I say something?

What if she wants to keep it? I don't think that would be the case, but it would start a fight because, as a female couple, we obviously don't need a pregnancy test. I know I am overthinking this, and I could use some advice on how to handle this uncomfortable situation. -- SURPRISED ABOUT IT

DEAR SURPRISED: I'm glad you asked. Do not "quietly" throw out those pregnancy tests or the medication. I don't know what kind of arrangement you have with your live-in girlfriend, but if fidelity was part of the agreement, you should absolutely talk with her about what you found. It does not have to degenerate into a fight, but it's important that you know why she feels the need to be in an intimate relationship, regardless of gender, with someone else.

DEAR ABBY: My husband and I have a wonderful life and much to be thankful for, but we have no children and are usually alone on Thanksgiving and Christmas. Everyone makes such a fuss about sharing these holidays with loved ones, but I become depressed during this season.

I do volunteer work on these holidays, but still feel sad and like everyone else in the country is having a better time than I am. Any suggestions? -- NOT SO JOLLY IN ARIZONA

DEAR NOT SO JOLLY: You must be a new reader of my column or you would know that every year around holiday time I receive letters from people like you, expressing that rather than feeling joyful and elated, they feel depressed and deprived. Some of it may be the result of the incessant marketing of these holidays, which gives the impression that "everyone" is having a grand old time sipping cider, stuffing themselves with turkey and caroling under the windows of their neighbors.

An antidote for your holiday blues might be to do more than volunteer. Why don't you and your husband plan to do something special to treat yourselves, rather than stay home feeling like everyone else is enjoying themselves? Choose a different destination each year to visit and learn about.

Or invite some friends or acquaintances to join you at home. There's a saying that misery loves company, and in your case, company might be the solution to the problem.

DEAR ABBY: After my future son-in-law moved in with our daughter, my husband and I stopped by unannounced to visit. He answered the door in his underwear and never bothered to go put on a pair of shorts. We didn't say anything and, of course, didn't stay long.

It was close to Christmas, so we bought him a robe and my husband jokingly told him, "We figured you didn't have one since you stay in your underwear when we're here." Even after that, he still does it.

I finally told my daughter, "Since he can't take a hint, please tell him to put on clothes when I'm coming over." Since then, when we've stopped by (dropping off the grandbabies) he still doesn't put shorts on.

It happened again today. I asked him to please throw on some shorts, and his response was, "You're killing me in my own house," but he did do it. They rely on us to help with our granddaughters, but I'm fed up with having to see him in his underwear. I also don't think he should go around that way around his 6-year-old stepdaughter and his 2-month-old daughter. What are your thoughts on this? -- HURTING EYES IN FLORIDA

DEAR HURTING EYES: Because you are doing your daughter and her husband the favor of looking after the grandkids, and you have let them know you prefer not seeing your son-in-law in his undies, your wishes should be respected. However, different families have different standards regarding attire around the house, and you shouldn't judge him for what he chooses to wear in the privacy of his home when you are not around.

DEAR ABBY: My 8-year-old daughter keeps asking me for a smartphone. I'm at a loss about who she would call besides me and her dad. She points out these different kids her age who have phones. They are the same kids I view as ones who will have no curfew, boyfriends at 12 and parents who aren't as involved as we are. At what age do you feel kids should have smartphones? -- INVOLVED PARENT

DEAR INVOLVED PARENT: I don't think there is a magic number, but your daughter is definitely too young to have one. Smartphones can be dangerous when they are used irresponsibly. A flip phone, perhaps, for her to contact you in case of emergencies, might be appropriate.

Because her friends have smartphones is not a valid reason for her to have one. Before that happens, you must be confident that it will be used responsibly, and that you and her father will be able to review its history.

DEAR ABBY: Could you help all of us guys named Shelby spread the word that Shelby is not just for the female gender? Many boys and men like me have the handle and are proud of it. -- SHELBY FROM TEXAS

DEAR SHELBY: So do some automobiles! I'm glad to relay your message. Today many women have names that were once associated only with the masculine gender -- Cameron, Bailey, Logan, Morgan, to name a few -- and turnabout is fair play. I'm reminded of the song "A Boy Named Sue."