DEAR ABBY: I'm 27 years old. When I was 18, I got married because my girlfriend was pregnant. We're now divorced, and my son lives with me because my ex refused to be responsible for him. She ran off with her new boyfriend.

I have just learned that my son isn't really my son after all. My ex finally admitted to me that she had always known he wasn't mine, and that his real father died of a drug overdose in 1996. A DNA test will prove it this week.

I'm extremely frustrated because I don't feel I should have to take care of a child who isn't even mine. I love the boy, but I don't feel he's my responsibility anymore. I was tricked into being his father. I wouldn't have taken the job had I known eight years ago that he was someone else's.

We have a very close relationship and I take good care of him, but I would like to live my life for myself and do what I want when I want -- like his mother does. I can't do that because he's my responsibility.

I know he needs me and loves me, and I'm afraid of what it would do to him if I sent him to live with his mother so I could live my life. I'm so confused, Abby. Can you give me any advice so I can compromise my desires and his needs? -- USED IN NORTH CAROLINA

DEAR USED: The last thing you should do is send the boy to live with a woman who has already proven she's an unfit mother.

You are young, and you're feeling overwhelmed with responsibility. However, quitting is not an option, and I doubt you could live with yourself if you tried it.

You need time for yourself -- every single parent does. If at all possible, arrange for relatives or close friends with children to invite your son to stay with them for an evening or a weekend once or twice a month.

Another alternative would be to find a single-parent support group in your area. Parents Without Partners is a good one. You can contact the organization by calling (800) 637-7974 or visiting the Web site: www.parentswithoutpartners.org.

DEAR ABBY: When my beloved transferred pictures and cards to a new wallet, he found a clipping from an old Dear Abby column. He'd carried it for ages. Unfortunately, it is tattered, frayed and worn away around the folds.

Abby, please reprint it. We would like to share this philosophy with others in our crowd. We celebrated our 80th birthdays this year. Sign us ... STILL IN LOVE IN TEXAS

DEAR STILL: I've received several requests to reprint that letter. Read on:

DEAR ABBY: Please explain the difference between "making love" and "having sex." A lot of people confuse these two very different acts. Will you please define each one? -- JUST PLAIN BILL

DEAR BILL: In "having sex," the name of the game is sexual gratification. It's a selfish, physical exercise in which the partner can be a faceless object. (Anyone will do.)

In "making love," one is motivated by a desire to give pleasure, express deep affection and communicate one's feelings of caring. It's the ultimate in sharing. In "making love," the partner must be a very special person. (No one else will do.)

Love is a metropolis. Sex is a whistle-stop.

CONFIDENTIAL TO MY READERS: Have a Merry Christmas, but keep in mind: If you're drinking, don't drive; if you're driving, don't drink.

Abby shares her favorite recipes in a two-booklet set. To order, send a business-size, self-addressed envelope, plus check or money order for $7.90 per set ($9 per set in Canada) to: Dear Abby Cookbooklet Set, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)

DEAR ABBY: I almost had a heart attack when I opened my phone bill. It was more than $800. I called the phone company and told them it had to be a mistake. To make a long story short, it was because of our computer-access phone number.

We recently moved 60 miles away. We were supposed to change the access phone number to a local number, but we didn't because we don't know much about computers and didn't realize we should. After talking to the telephone company representative, we changed access numbers, but not before the next billing cycle -- and we received a phone bill for another $800. This bill cannot be negotiated, so we are paying it in monthly installments.

Abby, please warn your readers to be sure they change their access phone numbers for their computers if they move. Otherwise, they will receive the shock we did. -- SORRY, WRONG NUMBER

DEAR SORRY: Yours was an expensive lesson. I hope that readers will learn from your eye-opening experience, and not procrastinate about changing their access number when the need arises.

DEAR ABBY: Could you please, please publish a letter in your column in which the age gap between a man and a woman is in the "other" direction, i.e., the wife is older than the husband? There are a lot more older women than men in the United States.

Thank you, thank you, Abby. -- SYLVIE IN PLANTATION, FLA.

DEAR SYLVIE: I happen to have just the thing. It arrived in the same batch as your letter. Read on:

DEAR ABBY: My wife and I are celebrating our 21st wedding anniversary today. My wife is 72 and I am 43. I'm not going to claim it has always been a "bed of roses," but we are quite happy with our life.

We have no children together, but I have two wonderful stepdaughters and one fantastic 3-year-old grandson.

I believe that everyone who knows us -- including the ones who doubted my intentions -- will agree we are a very compatible couple. Most people thought I was marrying her for her money. That's a laugh, considering I had more than she did. -- A NOTE FROM THE "OTHER SIDE"

DEAR "OTHER SIDE": Best wishes to you and your wife on your anniversary. Nowhere is it written that the husband "must" be older than the wife. In fact, my husband is six weeks younger than I am -- and it hasn't bothered either of us a bit.

DEAR ABBY: The letter from "Ticked Off in Louisiana," who was concerned by the many thumbtack holes resulting from his stepdaughter's posters, brought back a fond memory.

When our teen-age daughter wanted to paint one wall of her bedroom black, I choked and sputtered, but I didn't criticize. My wife and daughter spent a memorable afternoon together painting and redoing the room. I was enlisted to remove the bed frame so she could have her mattress on the floor. She loved it. She was the envy of her friends, who chorused, "What cool parents!"

When our "baby" left home a few years later, I spent a bittersweet afternoon repainting her bedroom. It was a four-hour trade-off for a precious memory and an ongoing relationship with a daughter who is loving, respectful and cherished.

Someone once said about running a company, "Take care of the little problems, and the big ones will take care of themselves." It works in life as well. -- SAN DIEGO DAD

DEAR DAD: I agree with that philosophy. Since the letter from "Ticked Off" appeared in my column, I have been inundated with mail. Readers inform me that there are now adhesive products that allow posters to be displayed without damaging walls. I received samples of two products offered by 3M that feature Command Adhesive, which the company claims will come off cleanly without damaging the surface of the wall.

To receive a collection of Abby's most memorable -- and most frequently requested -- poems and essays, send a business-size, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby's "Keepers," P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included.)

DEAR ABBY: I am a teen-age girl, and there is this guy at my school. He asked me out on a date. I don't know what to say. I really want to go, but I'm afraid that my friends and others will make fun of us because he's a year younger than me.

And there is one more problem: He is my best friend's brother. I'm not sure -- but I "kinda know" -- how she's going to take it. But what should I do about my friends? I know my best friend is going to take it well, but I don't know how my other friends are going to take it.

So what should I do? Signed ... ONE OF YOUR FANS (MANDY)

P.S. I read your column every time it's in the paper.

DEAR MANDY: You must decide what's more important to you, pleasing yourself or pleasing your other friends. If the choice were mine and I was teased because I went out with someone a year younger, I would reply, "Well, I LIKE him, and I think he's very cute." There are times you have to stand up for what you believe in.

DEAR ABBY: After five years of marriage, I find myself in the middle of divorce proceedings. I'll spare you the gory details, but suffice it to say that my wife left me for a co-worker. Luckily there are no children involved, so other than the emotional pain, the process is primarily financial at this point.

As part of the proposed settlement, I am responsible for returning the personal effects she left behind when she abandoned our home. Most items are easy to deal with, such as clothing, shoes, etc. However, other things are causing a dilemma for me. These are the items that have a connection with our marriage. In particular, I'm troubled by what to do with our wedding album.

In one sense it represents a part of my life and my family history, even though it's been painful. On the other hand, the album is a reminder of the failure of our marriage and the promises that we made to each other. Its financial value is virtually nil, and she has not explicitly requested its return. I want to do the right thing, but not at the expense of my own well-being.

Abby, can you please offer your thoughts on how to deal with this while still remaining a gentleman? -- FEELING TORN IN PITTSBURGH

DEAR FEELING TORN: With pleasure. If you want the album, keep it. Your (almost) former wife can order copies from the photographer who took the pictures.

DEAR ABBY: My mother-in-law baby-sits my 2-year-old son once a week. She is a chain-smoker, smoking one cigarette after another while our son is there. When he returns home, he is saturated in smoke, and I have to bathe him immediately and wash his clothes. He has complained twice that his eyes hurt. For obvious reasons, I do not want him around all that smoke.

Unfortunately, in my husband's eyes, his mother can do no wrong. Abby, is there anything I can do? -- HATES TOBACCO IN TENNESSEE

DEAR HATES TOBACCO: Talk to your son's pediatrician and ask him to schedule an appointment that includes your husband.

Secondhand smoke IS dangerous for babies and small children, and your husband should be made aware of the risk that his son is facing at the home of his chain-smoking -- and obviously addicted -- grandmother.

CONFIDENTIAL TO EDWARD JAY: Happy birthday, son. Your father and I are so very proud of you.

For an excellent guide to becoming a better conversationalist and a more attractive person, order "How to Be Popular." Send a business-size, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby Popularity Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included.)