DEAR ABBY: In October l986, my father was diagnosed with terminal cancer. My mother nursed him at home after surgery revealed there was nothing more the doctors could do for him. He was not the ideal husband or father. He had been an alcoholic for 10 years, during which he missed all family events, including my high school graduation. My mother refused to leave him, saying he would only end up homeless on the streets.

After battling the cancer for three painful months, Dad died on New Year's Day. Needless to say, his passing was very hard on Mother. At the end, my father told my mother how sorry he was and thanked her for being such a good wife to him.

A few days before his funeral, Mother decided to go to the bank at the mall to deposit $200 in cash and checks that friends and family had sent us, and which we desperately needed. She stood outside the bank filling out her deposit slip when she realized the bank had not yet opened, so she decided to return the next day.

A few hours after she returned home, there was a knock at the door. I answered it and was greeted by a young couple who explained they had found cash and checks on the counter outside the bank in the mall. In her grief, Mother had left behind her deposit! The couple found her address on her deposit slip and drove around but couldn't find the street. After stopping at a few gas stations for directions with no luck, they finally had to stop and buy a map. They handed me the money, and my mother stood speechless. When I closed the door and turned around, tears were rolling down her face.

We still talk about that incident, wishing we had taken the name and phone number of that young couple. They never knew how much their act of kindness has meant to us. Since then, if we find anything of value, we try our very best to locate its owner. We hope that unselfish couple reads this, because we'd like to finally say thank you. -- ESTHER AND LETICIA WHITAKER, SAN JOSE, CALIF.

DEAR ESTHER AND LETICIA: Thank you for your heartwarming letter, which illustrates that making time to do the right thing can make a world of difference.

DEAR ABBY: Our daughter and her husband visit us often with their darling baby girl. The problem is our son-in-law seems to think it's great fun to play "tickle-tickle" with our granddaughter, who is only 3 months old. He tickles the baby constantly, and we cringe every time he does. To us, it looks more like torture.

How can we tell our son-in-law, without hurting his feelings, that we think his behavior is not good for the baby? -- CARING GRANDPARENTS, NASHUA, N.H.

DEAR CARING GRANDPARENTS: Your son-in-law is uninformed about the effect tickling has on babies. He most likely considers his actions playful and harmless, but doctors say that excessive tickling stimulates infants inappropriately and instead of experiencing pleasure, they experience pain. Show this column to your daughter, and ask her to have a talk with her husband.

To receive a collection of Abby's most memorable -- and most frequently requested -- poems and essays, send a business-sized, 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, Ill. 61054-0447. (Postage is included.)

DEAR ABBY: You have printed many letters from the "other woman" -- who is always hurt because her married lover won't leave his wife for her. Well, here's one from the married lover.

I am a male who is almost 50 and have been experiencing one hell of a midlife crisis. My wife has wanted a divorce for about a year now, and somehow I keep convincing her to hang in with me.

I got involved with my younger secretary. She knew just what she wanted -- me. She left her husband. I never asked her to or promised her anything; in fact, I tried to talk her out of it. I have broken off our affair, but she won't stop calling. She has played dirty, calling my wife and sending her ugly notes.

Abby, I have a devoted wife who still loves me. I'd have to be an idiot to leave her for a younger secretary whom I don't really know. My secretary wouldn't have liked the real me who my wife has put up with for 27 years. My wife did everything I wanted all these years. I insisted she stay home with the children, and then I became unhappy with her when all along it was me I was really unhappy with. I can only pray she forgives me someday.

Abby, we married men don't leave our wives because we're not crazy -- we just act that way sometimes! I know this is a long letter, but please print it anyway because it needs to be said. -- DAVE IN MONTANA

DEAR DAVE: I'm printing your letter in its entirety because every woman involved with a married man is convinced that her romance is the exception. Perhaps your letter will wake up a few dreamers.

The damage to your marriage may take some time to repair. Counseling may speed up the process and help restore the trust that's been violated. Good luck to you and your wife.

DEAR ABBY: My friend and I belong to the same organization. Recently her husband was arrested for fraud and absconding with funds from his employer. He was found guilty and is now serving time in prison.

Whenever I see this woman, I want to ask her how her husband is, and how she's doing. I am truly concerned about her welfare, but I don't know whether it would be appropriate to ask her since she has never spoken about it. I learned that her husband went to prison when I read it in the paper.

I don't want to offend her by asking. Your advice would be greatly appreciated. -- IN DOUBT

DEAR IN DOUBT: When you see your friend, ask her how her husband is doing -- it will open the door for further conversation concerning his incarceration should she want to talk about it. You will know by her response whether she appreciates your having asked about him.

If any of my readers have experienced this situation, I would like to hear from them. I will keep your identity confidential.

DEAR READERS: Your chuckle for today: "I learned everything I know at my mother's knee. It was heavily tattooed." -- WOODY ALLEN

What teens need to know about sex, drugs, AIDS, and getting along with peers and parents is in "What Every Teen Should Know." To order, send a business-sized, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby, Teen Booklet, P.O. Box 447, Mount Morris, Ill. 61054-0447. (Postage is included.)

DEAR ABBY: I lost my virginity in my mid-teens to a young boy who then informed me that he already had a girlfriend. In the 15 years since, I've had dozens of failed relationships. They were all characterized by the same mistake: becoming intimate too quickly!

To cope with the pain, I either jumped into new relationships in order to forget, or abstained from them for years. Alternating between pain and loneliness is not much of a choice.

I'm well-educated and pretty sharp about a lot of things, but I was slow to slow down. While my own painful experiences cannot be erased, perhaps parents and young people can be made more aware that the music, media and the lack of family involvement carry our relationships along at speeds detrimental to our physical, emotional and mental well-being.

Last month I began dating a delightful man. We have spent many hours talking and laughing without revealing more about ourselves than makes us comfortable. And we have done no more than hold hands. It is by far the sweetest relationship I have ever known. -- WISER NOW

DEAR WISER: It takes courage to examine the reasons we behave the way we do, and you are to be commended for it. That which is truly worthwhile requires time and effort.

DEAR ABBY: My husband has a sweet nature, but he talks too much. The older he gets, the more he talks. He's 56, and I'm afraid he's headed for a very lonely old age. Any suggestions? -- CONCERNED WIFE

DEAR WIFE: I could write a sermon on the subject. Allow me to quote from my booklet "How to Be Popular":

"The person who comes into your company and does all the talking is no less a hog than the person who comes to your table and eats all the food. Do not dominate the conversation.

"Don't feel that every moment must be filled with conversation. Take a little time out to think and reflect. Moments of complete silence can be relaxing. Don't interrupt when someone else is talking. It's rude. And if you have to raise your voice to be heard, the chances are nobody will listen to what you have to say anyway.

"Believe it or not, being a good listener will do more for you than being a good talker. If you want to make a hit with someone, ask him or her questions. People enjoy talking about themselves. Give them a chance, and they'll think you are a great conversationalist!"

DEAR ABBY: My husband and I are having a disagreement. We live in a military community and my husband is a retired naval officer. He insists that our 12-year-old daughter address retired and/or active duty military personnel by their rank, e.g., "Lt. Browne."

We have taught her to address adults as Mr., Mrs., Ms. or Dr., but I don't believe it should be extended to ranks in the military. I think it's difficult for her to remember what a person's rank is. What do you think? I told my husband I would write to you and abide by your decision. -- PERPLEXED IN SILVERDALE

DEAR PERPLEXED: I agree with your husband. A 12-year-old (especially the daughter of a naval officer) should have no trouble remembering the rank of her father's fellow officers. And if she is in doubt, she could ask her parents.

For an excellent guide to becoming a better conversationalist and a more attractive person, order "How to Be Popular." Send a business-sized, 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, Ill. 61054-0447. (Postage is included.)