CHRISTMAS TIME IS the season for husbands to disappear. I don't mean that they aren't around to help with gifts, cards, baking and the rest of the holiday work. What I mean is that they seem to disappear right off the face of the earth.

Every year we get cards from people we haven't seen all year, with bright little messages like, "Best wishes for the holiday season, hope we can get together real soon," and signed, "Elizabeth and the kids." Now when last seen or heard from, Elizabeth and the kids had been accompanied by someone named Ralph who, as far as the world knew, was a reliable husband and father to Elizabeth and the kids. Then Christmas comes one year and bang: He's gone without a trace. Now if this puts Elizabeth and the kids in a sorry state, think about the rest of us who have a Christmas card acquaintance with this family. Whatever happened to Ralph?

If Ralph had died, we would have heard. Of course, if the Ralph in this story lived in another city we might have missed the obituary, but then Elizabeth might have had the smarts to realize this and given us a clue. Christmas cards aren't the place for bad news, but if Elizabeth wants to continue our Christmas card correspondence, the least she could do is note that Ralph passed away in August and tell the circumstances. Briefly. But Elizabeth is no dummy. She knows this and we know we're only kidding ourselves when we talk about Ralph passing on.

Ralph didn't pass on. He walked out. You just know , when the card comes signed "Elizabeth and the kids," that Elizabeth and Ralph have split and that Elizabeth, being a woman of impeccable taste, knows that you don't put news like that on a Christmas card. So here we are, opening the card and discovering Ralph has disappeared and leaving us with our conjectures. Did he walk out? Did Elizabeth throw him out? (He always seemed a little difficult to get along with). Did he have his mid-life crisis and fall in love with another woman and, rat that he is, leave poor Elizabeth with four kids and a broken heart? Or did Elizabeth and the kids leave Ralph for another man? (A lot of this scenario varies, depending on whether the husband or wife is opening the card at the other end, and whether, in fact, the wife at the other end has a husband herself.)

Your only clue is the envelope. Return addresses tell a lot. If it's the same as the address where you sent their card, then it means that Elizabeth and the kids at least still have the house. It may also mean that Ralph is just going through a phase and that he will grow up and return home. If Elizabeth will take him, that is. But if the return address is different from the one you have, that means real trouble in the marriage. It may mean that Ralph took the house and left Elizabeth and the kids out in the cold, but that's not likely. Remember, Elizabeth is no dummy. No, the odds are that it means they have sold the house, split the proceeds and each gone to take up residence in their new lives, Elizabeth with her broken heart, and Ralph with his Lolita.

But who knows?And what, for heaven's sake, will happen the next time you meet up with Elizabeth. What do you say? "Hi, Elizabeth. Whatever happened to Ralph?" is not the most diplomatic conversation opener, but it is certainly the first thing that will pop into your mind when you next see Elizabeth.

Part of this whole problem with disappearing husbands is that they leave wives behind who continue to write Christmas cards because that's what they are expected to do. Have you ever gotten a Christmas card from just Ralph?

The first time we got a card from a woman with a disappearing husband, it occurred to me that some of this could be handled by tastefully done divorce or separation cards. Something like this: "Ralph and Elizabeth Jones announce their separation. (Do not say, 'are pleased to announce!') Elizabeth and the children will continue to reside at the family home, while Ralph will be moving to . . ."

There is no need to provide gory details, because everyone who gets the announcement will immediately feel that they can ring up Elizabeth and get the full story, or at least her version of it. The trouble with this solution, of course, is Elizabeth probably won't want to tell the whole world that Ralph has walked out when he first walks out, and by the time she feels like mentioning it to anyone but their closest friends, it is, you guessed it, Christmas time.

The obvious solution to all of this is to keep in better touch with one's friends so that these life-altering episodes don't have to be announced, however obliquely, on Christmas cards. But that is the kind of resolution most often honored in the breach. So maybe a solution is to give just a little more information on the Christmas cards, as did one of my friends, who at least had good news: "Hope you are well and enjoying the season," she wrote in a bold hand."Children and I are fine and so is my new life. I remarried in November and we are very happy. Take care."

I wonder whatever happened to what's his name?