I Do : (I Don’t. I Do. I Don’t. I Do.) : Don and Hope Schubert have married each other four times since 1986. They’re not alone; more couples are taking repeat trips down the aisle.

Call it serial monogamy, conjugal succession, multiple remarriage or rerun time.

It’s what happens when a man and woman fall deeply, passionately in love, then out of love, then in love again--sanctifying each mood swing with a legal maneuver that renders them either married or divorced. Again and again. To each other.

Sounds like bedroom farce to you? To Neil Simon, too. That’s why the Pulitzer Prize-winning author wrote a zany film (“Marrying Man”) about a tycoon (Alec Baldwin) who falls in and out of marriage with a singer (Kim Basinger).

Four times.

Artistic merits of the movie aside, Simon’s fantasy seems to have strong basis in fact.

When Disney Studios placed a small newspaper ad looking for “real people” who had remarried each other multiple times, hundreds of replies flooded in, a studio spokesperson says. (Disney asked some couples who answered the ad to help promote the film.)

Playwright Simon is on a long list of celebrities who have married and remarried the same partner: Don Johnson and Melanie Griffith, Larry King and Julie Alexander, Dick and Linda Smothers, Elizabeth Taylor and Richard Burton, Colleen Dewhurst and George C. Scott, William Saroyan and Carol Marcus, to name a few. Simon wed Dianne Lander in 1987 and 1990, at which point he told The Times, “It’s nerve-racking. Is it going to work again? Will we make the same mistakes?”

One crucial question he didn’t ask: Why risk the agony of a relationship that has failed once before? Why not start fresh, with someone new?

Simon, still in wedded bliss with his third and fourth wife, understandably declines to reply. He answers on film, however, with a couple so sexually attuned that not even divorce after divorce can pry them apart.

Ken Minyard, genial co-host of KABC’s morning drive-time show, has been married and divorced from the same woman twice.

Minyard, too, declines to discuss his personal life, but he says, “Generally speaking, it’s reasonable to assume that the qualities which drew you to a person the first time could draw you to that person again.”

Sure, but only offbeat show-biz types would marry each other again and again, right?

Not necessarily.

Although no statistics exist on how many marriages involve people who have married each other before, the number of remarriages in this country has increased 63% since 1970, to more than one million each year.

The National Center for Health Statistics reported that in nearly half of all 1989 marriages, at least one partner had been married before.

It seems only logical that some are repeat performances--couples who are marrying each other again and again until they get it right.

Don and Hope Schubert of Crossville, Tenn., are part of the statistical group.

Hope, 24, and Don, 28, have married each other four times since 1986.

“That is, if you don’t count the annulment,” Hope says.

“We annulled our third divorce, which made us remarried. Then, at the end of that year we un-annulled the divorce, which made us single again. Then we married again this year.”

Don, a police officer, explains: “We’re both very impulsive, and cops have a real high divorce rate anyway. It was never drugs, alcohol or other women that tore us apart. It was just that we’d fight about stupid things.”

The fights they had while married were nothing compared to their fights while divorced. “We’d argue about specifics of the settlement until we’d realize how stupid it was and that we really love each other,” Don explains. “Then we’d decide to get married again.”

Hope says, “Our marriages are wonderful; each is better than the last. We are never going to get divorced again.”

Both believe in true love: “What else could it be?” Don asks. “I’ve tried to figure this out, and I can’t. I just know I couldn’t give this much energy and devotion to anyone else in the world. If it weren’t true love, we wouldn’t try this hard to work things out.”

Andrew Christenson, professor of psychology at UCLA, believes that a lot of marital struggles concern trivial matters that look huge to the people involved: “Often the details of conflict have to do with things like how one spouse greets another, how much emotional support is given during a tense time, whether the spouse pays enough attention to his or her in-laws.”

These things can escalate into major problems that suddenly look much smaller and more fixable after the couple has separated and gained perspective.

“Suddenly, the separated couple starts missing all the good things about each other that attracted them in the first place,” Christenson says.

He emphasizes that “there are no empirical data or even any major theories on the subject of people who remarry each other. Everything here is speculative.”

But Christenson theorizes that the way people go through a separation or a divorce may influence whether they can ever reunite; some divorces and separations are extremely destructive, he says.

One spouse may clean out a joint bank account because he or she suspects the other spouse is preparing to do the same. A wife may refuse to visit her husband’s elderly parents at Christmas, even though it’s a family tradition and she knows it would mean a lot to him.

“The couple starts engaging in more and more extreme acts that make returning to the marriage almost impossible,” he says.

It leads both spouses to feel they could never trust each other again or go back to someone who does such cruel things. Slowly, one by one, these hostile acts seal the marriage’s fate.

“People who are able to remarry each other may be those who never got to such extreme levels,” Christenson suspects. They are able to resume the relationship with dignity, because they have not violated each other’s sacred trust.

Pam and Jim Buchanan of Kalamazoo, Mich., began their marital odyssey 26 years ago.

“We met at the local drive-in restaurant in 1965, when I was 16,” Pam says.

“We clicked, and we knew it the minute we met.”

They married a year later, when Jim was 18, and stayed together 2 1/2 years before they divorced.

“It was the 1960s,” Jim explains, “and people were out there having fun. I was tied down with a wife and child and all the stresses of a family.”

He mistakenly thought he was missing something, he recalls, and asked for a divorce.

They started dating again almost immediately. “We missed each other,” Jim says, and other women didn’t fill the bill. Pam says she never stopped loving him and never wanted the divorce.

They remarried 10 months later and stayed together until 1982, when she was 34, he 35.

By then, she had finished school and was about to begin teaching; he owned a home-security business.

“We had bought some land and were going to build our dream house,” Jim says. “It was a house we’d planned for years. But it became too much. I’d go to work at 7 a.m., come home at 4:30 p.m. and work on the house until 10:30 at night.

“I did this every day; weekends I’d start on the house at 8 a.m. and not quit until 10 at night.

“This went on for four years. By the end of that time, we had the house, but there was no marriage left.”

Jim says the project “brutally slaughtered and bludgeoned our marriage until there was nothing left. It killed the passion, the will, the desire. There was no energy left for anything.”

When the house was finished, they divorced. He moved into the new place with their daughter, then 16; Pam moved into town with her two cats and “learned to live on my own” for the next seven years.

It was a necessary experience for both, they now say. Pam had gone straight from her parents’ home to her husband’s and needed to experience her individuality. Jim says he realized how immature he had been: “I finally found my smarts and realized what the important things in life are.”

What are they?

“They are Pam,” he says.

The couple remarried in May, 1989.

“There’s no question we’ve got it right this time,” Jim asserts. “We did a lot of growing up while we were apart. Now there’s no ambivalence; there’s burning passion again. It never really left. It might have been dormant for a while.”

Constance Ahrons, psychology professor at USC and author of “Divorced Families” (W. W. Norton), says she’s noticed an increased number of divorced couples who, like the Buchanans, have remarried each other and lived happily.

But “getting back together with an ex-spouse or an old flame can be doomed unless the couple has dealt with the issues that caused them to split up in the first place,” she says. “The whole new genre of self-help books seems focused on addictive relationships, co-dependency and those kinds of issues” because a lot of people are caught up in the subject right now.

She believes only “to some degree” in the curative powers of love. The real cure, she says, is to work out past problems before they crop up again.

Elaine Leader of Thalians Mental Health Center at Cedars-Sinai Hospital says she thinks people tend to be drawn repeatedly to the same types of relationships. The person we pick meets some kind of need in us, she says.

And if we don’t resolve why we married in the first place, she says, we can get a divorce and marry someone else only to find “that we have married essentially the same person all over again.”