DEAR ABBY: I am responding to "Been There in Iowa," the divorced mother of two who convinced her ex-husband -- even if he did nothing else -- to call the children once a week to tell them he loved them.

My parents divorced when I was 3. My sisters and I lived with our mother. For a few years we enjoyed regular visits with our dad, but then visits became less frequent. During my teens, I was lucky to see him for a few hours every six months or so, and there were no letters or phone calls between visits.

The infrequent visits I had with my father were very hard for me emotionally. I felt he was only making token appearances -- being a father when it suited him or when his conscience bothered him. Sometimes I cried when he brought me home, never knowing if it was the last time he'd ever want to see me.

I felt disappointed, angry, deeply hurt and unloved. At 16 I could no longer take the emotional roller-coaster ride and decided he should either be a real father and a regular part of my life or stay out of it completely.

For seven years I neither saw nor spoke to him, but in those years I did a lot of growing up. It wasn't until recently that I realized I didn't hate him anymore. I was finally able to let go of the hurt and resentment and allow myself to forgive him.

I wrote my father a long letter, explaining that there were things I needed to say to him, pouring out all my feelings about the parent he had been and how it had affected my life. I made sure he knew I didn't hate him -- I still loved him -- and he didn't have to write back if he didn't want to.

Abby, he wrote me back! He said he'd been needing to hear everything I told him. He accepted the blame for his failings as a parent and apologized for hurting me. He is not the same man he was before, and he wanted the chance for us to get to know each other again. He said he loved me! His letter lifted a 10-ton weight from my shoulders. We now write frequently. -- THANKFUL IN TEXAS

DEAR THANKFUL: Your letter proves the truth of several important life lessons:

1. People can change.

2. It's important to speak the truth because often people need to hear it.

3. The burden of hurt and resentment is usually more destructive to the vessel that houses it than to the person who caused it.

DEAR ABBY: If a woman is married and divorced, then marries husband No. 2, but it doesn't work out, so she is divorced again, then realizes that husband No. 1 wasn't so bad, and they remarry -- should the couple count wedding anniversaries from where they left off? Or should they start over? Also, is it OK to be remarried on their original wedding date? -- SECOND THOUGHTS IN PHOENIX

DEAR SECOND THOUGHTS: While it may seem romantic to remarry on your original wedding day, I'd recommend against it. You can't make a divorce and a second marriage "disappear" by pretending they never happened. Your recommitment to each other is a fresh start, and as such, the anniversaries should also start anew.

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

DEAR ABBY: I am a high school senior. With graduation day fast approaching, I have some pressing questions.

First, what are the rules of etiquette regarding sending invitations/announcements? Do I have to invite all the members of my family to my graduation party that is supposed to be for my friends? (I would rather not even see most of these relatives, but my grandmother is insisting that I invite them.)

Second, what is the best way to keep track of gifts, so I can properly thank the gift-givers?

Abby, I have been reading your column since I learned how to read and would greatly appreciate your input. -- POLITE SENIOR DUDE IN AMARILLO, TEXAS

DEAR DUDE: Ask your parents if you can have two separate gatherings -- one for family and the other for your contemporaries. (Try to give family members the benefit of the doubt. As you get older, their finer qualities may emerge.)

Write what each person gives you on the card that accompanies the gift. That way, you can easily keep track of who gave what when it comes time to send thank-you notes, because it's always a nice touch to refer to the gift in your note.

P.S. Best of luck to you, grad!

DEAR ABBY: My sister and I have both become engaged. We are very close and are considering a double wedding. Our fiances think it's a neat idea. I've never been to a double wedding and have no idea how it works. Can you please help us? -- NEWLY ENGAGED IN EL PASO

DEAR NEWLY ENGAGED: Double weddings are extra-special events -- and they can reduce expenses.

I discuss this topic -- and more -- in my booklet, "How to Have a Lovely Wedding." It can be ordered by sending a business-sized, self-addressed envelope, plus a check or money order for $5 (U.S. funds) to: Dear Abby -- Wedding Booklet, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in the price.)

However, since you asked about double weddings, I will offer some tips from the booklet:

Two sisters or close friends may wish to be married in the same ceremony.

They may share the same attendants or each may have her own maid of honor. Each groom will, of course, have his own best man.

If they desire, each bride may serve as maid of honor to the other bride, and each groom may serve as best man to the other groom.

The brides do NOT need to dress alike.

The costumes of the attendants should harmonize, although they need not be identical.

If the brides are not sisters, church and reception invitations must be issued separately.

The reception is usually given jointly, and either one or separate receiving lines may be formed.

DEAR ABBY: You printed a letter from a girl asking how to stop biting her fingernails. Although you listed some helpful suggestions, I would like to offer one that helped me to finally stop at age 45.

I sat down and tried to figure out WHY I kept biting my nails. I finally realized it was because I couldn't stand the feeling of a rough nail catching on the fabric of my clothing.

Now I keep emery boards -- from coarse to fine -- beside my favorite chair, in my purse, in my glove compartment and by the bed. If I feel a "snag," I immediately smooth the offending nail. It eliminates the "need" to bite. -- FORMER NERVOUS NAIL-CHEWER, SANDY, ORE.

DEAR FNNC: Thanks for the tip. I was amazed at the number of former nail-chewers who took pen in hand to lend a hand. Read on:

DEAR ABBY: Thanks to my high school teacher, Mr. Elich, who included some interesting lessons in personal hygiene in his biology class, I haven't chewed my nails for nearly 30 years. One day he asked us to scrape under our fingernails and look at what we removed under a microscope.

The area under the nails can collect some unhealthy "specimens." Coming face-to-face with them was enough to make me think twice about biting my nails. -- PETER, BAY VIEW H.S. CLASS OF '75

DEAR PETER: You hit the nail on the head. Yech!

DEAR ABBY: I, too, was a confirmed nail-biter. What finally stopped me was a job I landed as a teen-ager. I became an usher at the Roxy Theater. The job required my wearing an immaculate uniform, including white gloves. Soon after I landed the job, I noticed that I had nice nails. The gloves were what did it. I never bit my nails again. -- S.S. IN FLORIDA

DEAR S.S.: Your solution makes sense. Out of sight, out of mind.

DEAR ABBY: I am a former compulsive nail-biter. Finally, at age 24, I went to a manicurist and had acrylic nails applied over my bitten, sore nail stubs. Acrylics are impossible to bite, and I needed to do it only once in order to break the habit. Even now, at 46, I occasionally get that biting urge, and the only way I can curb it is to go back to the manicurist. -- JANE, FORT MILL, S.C.

DEAR JANE: I'm pleased it worked for you, but some people are even driven to chew fake nails. Years ago, I wore porcelain nails, and if the urge became strong enough -- I'd bite them. Thank heavens short nails are now popular. It was an expensive habit.

DEAR ABBY: I suffered shame and guilt because I couldn't stop biting. Finally, when I was in my 30s, I asked my doctor if he could suggest a cure. To my surprise, he talked to me about obsessive-compulsive disorder and prescribed a low dose of a very safe drug used by people with OCD. In three weeks my nail-biting stopped for good. -- FORMER CHEWER, KEENE, N.H.

DEAR FORMER CHEWER: A survey mentioned in the 1977 issue of Dental Management magazine, sent to me by Edwin T. Coleman, D.D.S., of Knoxville, Tenn., stated that one out of 12 adults is a nail-biter. It concluded that of all of the successful cures that people may use, the one common denominator is MOTIVATION. And with that conclusion, I agree.

Abby shares more than 100 of her favorite recipes in two booklets: "Abby's Favorite Recipes" and "More Favorite Recipes by Dear Abby." Send a business-size, self-addressed envelope, plus check or money order for $10 (U.S. funds)

to: Dear Abby -- Cookbooklet Set, P.O. Box 447, Mount Morris, IL 61054-0447. (Postage is included in price.)