Q.What are the rules for sending Christmas cards to old lovers or their families?

After 2 1/2 years, my girlfriend left me. I never had the chance to say goodbye or thank her parents for their kindness and generosity to me. Should I send them something? Or her? Or will it only remind them of things they'd rather forget?

It seems sad when the people you know and love the most must be forgotten. A.Miss Manners is a great believer in thank-you notes, but not to the extent of thanking your girlfriend for leaving you.

Christmas cards are customarily sent to old lovers only if you are 1) still friends, 2) not cured and hoping to rekindle the romance, 3) trying to point out that you are better off for being rid of them, in order to make them sorry. Neither of the latter two has a success rate worth the cost of the stamp.

Miss Manners agrees that it is sad, but warns you that even a polite note thanking her parents for their kindness will be interpreted as an indirect attempt at No. 2 or 3. Q.The etiquette problems caused by the proliferation of divorced and remarried families should be enough to keep you working double shifts during the holidays. Here's what happened to us on Thanksgiving.

My husband and I have been married for one year -- the second marriage for both of us. Charlie has two grown sons in their twenties who live out out of state. Both came to Thanksgiving with us and brought their girlfriends.

It was arranged ahead of time between Charlie and his ex-wife that we would host Thanksgiving dinner (she has her own plans for Christmas).

Wednesday night, after I had shopped for a fresh turkey and all the trimmings, we accidentally found out that the lady had prepared and served a full Thanksgiving feast -- turkey, et al. Unable to face the prospect of going through all that trouble only to duplicate a meal and set it in front of four already stuffed guests, I proposed to my husband that we serve something else.

As it was past 9 p.m., we were lucky to find six good steaks in our freezer. Both he and I were very disappointed, and I must say I took it hard, becoming furious and weepy by turns.

Needless to say, Thanksgiving was a subdued affair. Even though we put our best feet forward, everyone was conscious that there was something amiss. Little was said about the change in menu, and somehow we got through it okay.

Am I right in feeling the ex-wife was thoughtless in her choice of menu? Should I have taken it so personally? Should I have served turkey anyway? Finally, should I call her and tell her about my feelings? A.The turkey is not the problem. Miss Manners never thought of turkey as a subtle bird, but that's not what made the trouble.

The problem is adjusting tradition to the nontraditional family. It is all very well to agree to split the holidays between the parties to a divorce the way you split the property, but it is even harder to do. (And ask your husband if it was easy to split the library or the pictures.)

There is a great deal of emotion involved in family ceremony, and Miss Manners hopes you are not going to condemn someone for trying to salvage a bit of it for her own consolation. Even if her motive were to undercut your party, she would be more pathetic than mean. Let it go.

Redundancy is inevitable when the parents have separate households. Wherever the children dine on Christmas or their birthdays, you will each exchange presents with them and perhaps have your own little celebrations.

Therefore, Miss Manners would have gone ahead with the turkey. Everyone eats turkey at least two days in a row every Thanksgiving, anyway. At least your stepsons will get their seconds fresh and hot. 1985, United Feature Syndicate Inc.