DEAR ABBY: I just read your response to "Nameless in a Red State," who asked if she could become addicted to drugs by having sex with an addict.

You were correct to point out that it's important she stay away from people who are addicted to drugs if she wants to stay clean. I work in a methadone clinic. My clients know they have to be careful who their friends are. It is very easy to start using drugs again while in treatment if you're spending time around people who are using.

I was, however, disappointed that you didn't mention that having sex with a drug addict is a recipe for getting AIDS and many other sexually transmitted diseases. (I call it the gift that keeps on giving.) People must remember that when they have unprotected sex with someone, they are also having sex with everyone that person has had sex with. Latex condoms are the best defense against sexually transmitted diseases. -- R.N. IN BLUE NEW JERSEY

DEAR R.N.: I'm sorry you were disappointed that my answer didn't go far enough; however, the woman's question was, "Can I become addicted to drugs by having sex with an addict?" I answered her question factually and specifically.

I also heard from a physician who felt I should have elaborated further. Read on:

DEAR ABBY: In your reply to the writer, you failed to mention the most dangerous complications of such behavior, infection with potentially fatal diseases such as hepatitis B, hepatitis C or AIDS. There is a high incidence of these diseases among drug addicts because of the sharing of contaminated needles, and they can also be transmitted through sexual relations. -- ALEXANDER N. ZINN, M.D., WINNETKA, CALIF.

DEAR DR. ZINN: Your letter makes me wonder how many lives could be saved if clean-needle exchange programs were available in every city. Thank you for clarifying my answer.

DEAR ABBY: We had a houseguest recently who asked to use my computer to check on his airline flights. After he left, I went into the history to check out a previous site I had used and found my computer full of adult porn sites. These sites were surrounded by his airline reservations, so it could not have been anyone else using my computer.

I erased the sites and then cleared out the cookies, but now I'm getting reports from friends that they are getting adult porn pop-ups when I send an attachment. I will contact my Internet service provider, but I will probably need to get a new e-mail address.

My husband and I are not sure how to handle this. Should we tell him we know what he did on my computer, or do we just avoid him when he makes contact with us again? If I never see this person again it won't be a hardship. I feel violated. Any suggestions? -- PIQUED IN PALO ALTO

DEAR PIQUED: Your houseguest should be made aware of the problems his little surfing adventure have caused you. If it were me, I'd pick up the phone and give him holy heck for taking advantage of my hospitality in that way. If you want to avoid him in the future, it's certainly your privilege, but he owes you an apology, and you should collect it.

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 $5 (U.S. funds) to: Dear Abby -- Keepers Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)

DEAR ABBY: My ex-husband, "Greg," is being married in the fall to a wonderful woman I have come to regard as a friend. "Marla" is good to my two little boys. She pays their child support on time, attends every one of their school functions and sporting events, and loves them like they're her own.

I'm wondering if I should try to convince Marla not to marry Greg because he is very abusive. He has had problems with the law and was extremely violent during our marriage. I have the pictures to prove it. He even beat up my mother one time.

Members of Greg's family have told me he's already showing signs of being abusive to Marla. Should I voice my fears to her, or just be thankful there's someone there that I can trust with my boys? -- TROUBLED IN NEW JERSEY

DEAR TROUBLED: Listen to your conscience and tell her what she could be in for. Don't be heavy-handed about it. Just arrange a private get-together and tell her you would hate to see what happened to you happen to her. Then take out the pictures and show them to her. If the spousal abuse is mentioned in your divorce papers, share that with her, too. After that, the decision is hers.

DEAR ABBY: I don't drink and neither does my family. My fiance drinks on occasion, as does the rest of his family. We are being married in September, and I'm having a problem with the alcohol issue.

Abby, I don't want booze at my wedding. I have agreed to serve wine or champagne, but his family says nobody wants to drink just that, and that a wedding is no fun unless people are getting a buzz. I want my special day to be memorable, not an excuse for people to get drunk and pass out.

My father says if they want to drink hard liquor, they can have an after-party at their house. They already plan to do it, but they still insist that the wedding won't be any fun without booze. I have 2 1/2 months before the wedding, and I'm beginning to have second thoughts about going through with it. Your thoughts, please. -- SOBER BRIDE, BRANDON, FLA.

DEAR SOBER: If sobriety is important to you, you must realize that after your wedding you will be joining a family with a very different point of view from your own. That difference will be apparent during every family visit and celebration. People who can't "have fun" without drinking are alcohol-dependent, and you cannot change them. It's time to have a serious talk with your fiance about it, because this is an issue that could drive a serious wedge between you.

CONFIDENTIAL TO MY READERS: If you're looking for the "purrr-fect" gift for the cat lover in your life, I have the item. It's a fascinating, beautifully illustrated history of human-feline relationships, starting with cats' exalted status among the ancients as royal or sacred beings. The author is pioneer foreign correspondent, expert in international affairs and passionate cat-lover Georgie Anne Geyer, who traveled through the Middle and Far East to research the origins and characteristics of the 41 recognized modern cat breeds. The title is "When Cats Reigned Like Kings" (Andrews McMeel Publishing, $24.95). Available in bookstores, it's truly an "a-meow-sing" read!

DEAR ABBY: Your answer to Brenda in Lakeland, Fla., who asked whether she should leave dead pets buried in her yard when she moves to another home, was off base.

I thought my pets were safely buried under a tree five years ago when we sold our home. Two years ago, I drove by my old house and, to my horror, saw that the tree had been torn out and a swimming pool now sat where we buried my beloved "Prince." The poor thing probably ended up in a landfill or a freeway base. Fortunately, before we moved, I had dug up another precious dog and had his remains cremated. He will go with me when I go.

I urge anyone who loves a departed pet and who is moving to always cremate. With real estate as valuable as it is, you can't trust any land to remain untouched by developers. The house I grew up in was in the country in 1955. Million-dollar homes now sit on that same acreage. My advice is to cremate pets and have them buried with you when the time comes. -- WE'RE ALL GOING TOGETHER IN GARDENVILLE, NEV.

DEAR GOING TOGETHER: Please accept my sympathy. The responses I have received to that letter have been varied, but all have been heartfelt. Read on:

DEAR ABBY: I agree with you that the remains should stay where they are. However, I have a suggestion to offer that will help her feel as though her pets are still with her.

When my parents moved from our childhood home where our three family dogs were buried, my brother gathered some dirt from their burial site along with three large rocks. At my parents' new home, he buried the dirt and marked the spot with the rocks, representing each beloved dog. This way they are close to our family, while staying where they lived their lives. -- ALISON IN BOTHELL, WASH.

DEAR ALISON: Now that's what I call a workable compromise.

DEAR ABBY: Sorry, but I don't agree about leaving the pets buried in the back yard when the family moves. Imagine the trauma when the new owner's kids accidentally dig up one of them. Instead, they should contact their veterinarian or the health department about proper disposal of their pets. -- GUS IN WOODSTOCK, ILL.

DEAR GUS: Trauma? Much would depend upon how old the children were. A young child might be frightened; an older child might be curious -- especially if he or she was with friends when it happened.

DEAR ABBY: You advised leaving the pet's remains where they are. My husband and I couldn't bring ourselves to do it. When we moved three years ago, we exhumed our beloved schnauzer's remains (his ashes were buried in a container in our yard) and took the container and headstone with us. We find it comforting knowing he's nearby, and he now has a lovely new spot in our new yard. -- LU IN JACKSONVILLE, FLA.

DEAR LU: If his presence brings you comfort, more power to you.

DEAR ABBY: I buried my pet bird in my back yard many years ago and installed a concrete marker. That marker, dated June 1944, now rests in my daughter's garden, hundreds of miles away, and still looks as good as new. It no longer marks my bird's burial place, but rather a place in our family's heart. Your answer was perfect. -- LARRY IN EMERY, S.D.

DEAR LARRY: Your letter echoes one I received from Pam C. of Duluth, Ga., who wrote: "Tell Brenda to take the markers but leave the animals. The markers will mean nothing to the next owner, but they will bring her warmth every time she sees them in her next yard. I've been there and done that."

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-size, self-addressed envelope, plus check or money order for $5 (U.S. funds only) to: Dear Abby, Teen Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included.)