DEAR ABBY: April is Autism Awareness Month. I'm hoping that with the number of people your column reaches, you will help us in the autism community spread the word about the need for research and education about this childhood disorder.

Autism is a neurological disorder that severely affects a child's ability to develop communication skills and social interactions. The child lives in a world of his or her own. Its rate of occurrence has increased to about one in 400 children. Autism shows up around 18 months of age or older. It mostly affects boys, at a ratio of 4-to-1. No one knows what causes autism, and as yet there is no cure.

I have a granddaughter who has this disorder. The need for research is great because, with proper education, these children can improve and lead much better lives than they did 20 years ago. My granddaughter has improved a great deal in the 18 months she has been going to school. There, she is trained by teachers with special education skills to help these kids along.

Please help our growing community of autistic children by letting people know that if they need any additional information, they can contact the Autism Society. Thank you, Abby. -- ANDREA RUSSELL, NEW CASTLE, DEL.

DEAR ANDREA: I am pleased to help spread the message. Since I received your letter, I have learned that through hard work and intensive education, people with autism can hold jobs, make friends and lead fuller lives. Autism is the third most common developmental disability, and more common than Down syndrome.

People who would like to learn more about autism should contact the Autism Society of America, 7910 Woodmont Ave., Suite 300, Bethesda, MD 20814. The toll-free number is (800) 328-8476, extension 150; the Web address is: www.autism-society.org.

DEAR ABBY: The letter from "Grateful Survivor," who felt she was in love with a man who had rescued her from drowning, instantly reminded me of an essay, "The Chemistry of Love" by Diane Ackerman, that I use in one of my writing classes at California State University.

The essay explains the chemical underpinnings of such human experiences as falling in love, giving birth, responding to danger, and finding security in long-term relationships. Ackerman points out that the human body economically reuses some chemicals for many purposes. Such is the case with PEA (phenylethylamine), which gives an amphetamine-like "high" to new lovers and also surges during dangerous or thrill-seeking behavior.

According to Ackerman, the body's use of PEA "may help explain a fascinating phenomenon: People are more likely to fall in love when they're in danger. ... Danger makes one receptive to romance."

I'm no chemist, but it may relieve the happily married "Grateful" to know that what seemed like a puzzling and excessive response was caused by a chemical process over which she had no control. -- JOAN SPANGLER, ENGLISH DEPARTMENT

DEAR JOAN: That's fascinating. I have always wondered why couples found it "romantic" to be married while skydiving, bungee jumping or diving 20,000 leagues under the sea. Ackerman's theory provides a clue.

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, IL 61054-0447. (Postage is included.)

DEAR ABBY: My fiance and I are being married next year, and we have decided to start a new wedding tradition. Along with registering for housewares, china and place settings, we are requesting something straight from the heart of each of our guests.

We are asking our friends and families to donate blood in honor of our marriage! We want our guests to have the opportunity to give a gift that will truly last forever in someone's life. We have been donating blood together for several years, and it makes us feel great.

Our local blood center will set up a group number especially for our guests to use when they come in to give blood. They'll also keep track of the donations so we'll be able to personally thank each donor for his or her special gift.

Knowing that we have helped to save lives will add to the joy we will experience on our wedding day. -- BLEEDING HEARTS IN DENVER

DEAR BLEEDING HEARTS: I commend you and your fiance for your ingenuity and generosity. You've come up with a bloody good idea, and I hope it inspires others.

DEAR ABBY: I hope that 27-year-old married woman who told you she fantasized about kissing her "friend" will listen to what I have to say on the subject. I was the same age she is when I headed down that path, and I have a few tips I'd like to pass on:

Not only is that man not her friend, he's her enemy, her husband's enemy, and an enemy to her marriage. Long before she has ceased obsessing over that scoundrel, he will have forgotten her and moved on to his next victim. He will pull her down to his level until she has rationalized away her illicit behavior and no longer cares what it does to her marriage.

That little "adventure" will create in her a wandering spirit that no number of liaisons with him -- or the next suitor -- will satisfy. Her acquaintances will consider her loose and easy whether she consummates the flirtation or just plays around.

Full-blown affairs always begin with "harmless" little flirtations -- which are neither harmless nor little. While she's enjoying her trysts, she is robbing her husband of the mental, emotional and physical affection that is due him alone. The affair will leave permanent scars on her and her marriage that time will not erase.

How I wish someone had taken me aside and shared these facts with me. I was selfish and foolish, and have nothing to show for it but a divided and sorrowful heart. Abby, I hope she realizes before it's too late that it's up to her to direct her energies toward keeping her marriage alive and well, and that her husband needs her full attention. -- VOICE OF EXPERIENCE, PORTSMOUTH, N.H.

DEAR VOICE: I agree. The young woman who was tempted to act on her strong attraction to her "friend" is playing with fire. I hope she'll listen to you, if she wasn't inclined to listen to me.

For everything you need to know about wedding planning, order "How to Have a Lovely Wedding." Send a business-sized, self-addressed envelope, plus check or money order for $3.95 ($4.50 in Canada) to: Dear Abby, Wedding Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included.)

DEAR ABBY: On Nov. 18, 1991, the life of my 17-year-old daughter, Karen, ended far too soon. Karen was a beautiful and compassionate girl, always thinking of others and how she could help them. Just as she had in life, Karen wanted to help others in death by being an organ donor. She had signed an organ donor card, but never discussed the issue with me.

My fear and ignorance of organ donation almost hindered the fulfillment of Karen's last wish. A very sympathetic and knowledgeable professional explained organ donation to me clearly, and addressed the objections I had that I now know were based on myths. Because of him, Karen's death was not in vain, and four people, including a 9-year-old boy, were given a new chance at life.

April 16 to 23 is National Organ and Tissue Donor Awareness Week. Today, my goal in life is not just to educate people about organ donation, but to make them aware of how important it is to discuss their wish to be an organ donor with loved ones. In most states, the signed organ donor card is a legal document, but the next of kin is always asked for permission.

Karen left a legacy by giving "the gift of life" to others, and it has helped turn my tears of sorrow into tears of joy. These gifts have enabled recipients to celebrate transplant birthdays while my family and I celebrate Karen's life.

Abby, I hope your readers will join our crusade to make sure everyone who needs an organ transplant receives one. -- BARBARA MUSTO, NATIONAL KIDNEY FOUNDATION DONOR FAMILY COUNCIL

DEAR BARBARA: Thank you for your eloquent reminder.

Readers: Please think carefully about becoming an organ donor, so someone can have life when yours is finished. If you haven't already signed donor forms and notified your family of your wishes, I can't think of a more suitable time to bring up the subject than National Organ and Tissue Donor Awareness Week. For a free organ donor card and answers to the most commonly asked questions about organ donation, call the National Kidney Foundation's toll-free number: 1-800-622-9010.

DEAR ABBY: My fiance canceled our wedding two weeks prior to the wedding. We are going our separate ways.

I am uncertain what to do with the wedding shower gifts I received four months ago. My fiance and I bought a home, which I will continue to live in, and some of the items have already been used. My family and close friends have indicated that they do not want their gifts returned, but I am concerned about the other gifts we received. (Two wedding gifts received in advance are being returned.)

I feel as though I should at least offer to return the gifts or reimburse each person. However, I can't be sure who gave me exactly what. The cards and receipts were removed from the boxes, and the gift list prepared at my shower is not very detailed.

With the shock and devastation of my relationship ending, I am still worried about proper etiquette. Please tell me how to handle this. -- L.A. IN BETHLEHEM, PA.

DEAR L.A.: The best way to handle this is in a straightforward manner. Call the shower guests and explain that the wedding is off -- and that the gift list from the shower is not as detailed as it ought to be. Then ask what each person's gift was -- and if it has been used, offer to reimburse the money. I predict that most of the givers will refuse the offer.

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, IL 61054-0447. (Postage is included.)