COMMITMENTS : The Big Jilt : Hugh Grant did it. Dustin Hoffman made someone do it. Of course, it’s easy in the movies. But no matter how embarrassing the circumstances, it’s better to call off a wedding than be an unhappy spouse.

Guests, flowers, champagne, band. One smiling clergyman and one nervous groom.

After months of preparation, the stage is set and the cast is ready. But instead of “Here Comes the Bride,” the leading lady has opted for “Let’s Call the Whole Thing Off.”

Jilted at the altar. This is the stuff legends--and nightmares--are made of.

Hugh Grant said, “I can’t,” at the altar in “Four Weddings and a Funeral”; Courtney Thorne-Smith donned her wedding gown, took it off and fled before marrying Andrew Shue on “Melrose Place,” and in a scene that made movie history, Dustin Hoffman stole his loved one from under her groom’s nose in “The Graduate.”

The act is so devastating that, centuries ago, the Catholic Church was known to punish it with excommunication for the errant groom and exile to nunnery for the rejecting bride.

But no matter how embarrassing the circumstances, ‘tis far better to be a scorned fiancee than an unhappy spouse seeking a divorce.

“Thank God my wedding was canceled. I’d be divorced by now,” said Robert, 44, of Los Angeles, whose fiancee called off their wedding a week before the Big Day.

“We planned this incredible wedding on the beach. The invitations were out for 200 people. We had met the rabbi and planned the honeymoon. I went for a jog on a Sunday morning, and when I came back, I found her crying in the living room. She said very coldly: ‘Call your guests, the wedding is off.’ ”

Robert ranted, pleaded, practically groveled. When his intended asked if she could stay in his apartment--where she had been living for free--for another two months until she got a job, he finally got a grip.

“I said no way and gave her until Wednesday to move out. That same day I got on the phone and starting calling my guests. It was ugly, but I had to do it.”

Robert still doesn’t know what made his bride-to-be back out, and he admits that he was devastated. But in hindsight, he can see everything that was wrong about the relationship.

“The whole thing was my fault, because I should have seen it. She was more wrapped up in the wedding than in what the wedding meant.”

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Talking about expectations and goals in a marriage is a must for couples thinking about tying the knot, says Luz Patricia Bayer, a marriage, family and child therapist in Woodland Hills.

“Sometimes I ask people what they expected from marriage, and they have no idea,” she says. “They just know they liked each other. These are the marriages that end up having problems. . . . Couples that don’t think about what makes a good marriage and later realize that what they expected, or did not know they expected, isn’t there.”

What Patty Barrionuevo, 23, expected from her marriage was a husband she could trust. So when she caught her boyfriend of nearly five years cheating on her, she immediately called off the big wedding she had planned in her native Mexico.

“I found him in a hotel with a girl,” Barrionuevo says. “I saw his car parked outside and my friends started teasing me and saying, ‘Patty, what if he’s up in a room?’ I had my engagement ring on, and I went to the lobby and said I was his wife and it was an emergency. So they told me what room he was in.”

Not one to waste a dramatic moment, Barrionuevo not only got into a fight with the other girl, she also snatched up her boyfriend’s car keys and drove away in his car.

When she got home, she called his mother and told her the wedding was off.

“It was three months away and everything was ready, we even had a house,” recalls Barrionuevo, who has since married and separated. “My mom was upset because she really liked him, but I didn’t care what people said. The first thing that went through my mind was ‘I don’t want to be with a man I don’t trust. I’m out of here.’ And I left town, threw the ring away and gave my wedding dress away to a friend. And you know what? Her boyfriend canceled their wedding the day before.”

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A broken engagement is hard on both parties, says Sally Holguin, a marriage, family and child therapist with offices on the Westside and in Woodland Hills.

The jilted party “feels abandoned, not worthy of love. And public shame is always humiliating. For the person who breaks up it’s also shameful, because they feel they haven’t chosen intelligently and it makes them feel less like themself.”

The secret to success, Holguin says, is being authentic with each other, recognizing when something is wrong and addressing that problem.

Premarital counseling and marriage preparation courses can help determine what aspects of the relationship need to be worked on, because they bring up issues that might never be addressed.

Nevertheless, Holguin says, “you should never try to put a square peg in a round hole. People try to make up for the bad things, thinking the good will override. They know it isn’t right, but they often become too involved. Everyone gets the jitters, but it’s a different feeling or flavor from knowing someone is not what they hope they will be.”

Roger, 49, thought he had found his mate six years ago, a woman he describes as dynamic, intelligent and accomplished. But, “She was also an argumentative, confrontational person. She had troubling things, but we had a lot in common and I asked her to marry me.”

As their wedding date approached, her negative traits seemed to deepen, but “I felt I couldn’t go back on my decision,” Roger says. “I felt I’d made an emotional commitment and I didn’t want to hurt her. So you sort of let things go on but it gets worse and worse, because the wedding arrangements keep getting made. . . .”

Roger’s wake-up call came from several concerned friends, who told him flat-out that he was making a mistake.

“I realized I thought I would get a divorce. So three weeks before the wedding I postponed it, although as soon as I broke the news I knew it would never happen. It was a terrible experience. She was very upset; she was blaming me; she focused on the deposits she had put down, which I promptly paid.”

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The person who cancels a wedding at the last minute is far braver than those who go ahead with their plans even though they know they’re making a mistake, Bayer says.

“It’s such an enormous problem to call something off, emotionally and logistically, and to do that you have to really feel you don’t have a choice,” says Roger, who is now happily married and has a child.

Roger’s canceled wedding was admittedly not to have been a lavish affair, but Yvette’s was.

“To this day I don’t know how I got the nerve,” she recalls more than 15 years later. “I had the dress, the bridesmaids, the shower, the food, the hall. And the thing that sticks in my mind is I was absolutely miserable.”

He was her boyfriend of two years--charming, wealthy, considerate and obsessively possessive.

“He wanted to control my every movement and I thought I could change him. . . . But one Sunday we fought because I had gone out with my mom, and I thought, ‘I don’t care if I have to work five years to pay for this wedding,’ and I went to my mother’s room and said: ‘Mom, I can’t do it.’ ”

To Yvette’s surprise, her mother was relieved. “She just wanted me to decide for myself.”

Anyone who has major doubts should remember: It’s best to address them before the wedding.

“Speak with your fiance, go to premarital classes, go to therapy. If you can’t resolve your doubts, remember that it is better to cancel a wedding than to get a divorce, which is much more painful, expensive and damaging to your self-esteem.”

And save the champagne for the real McCoy.