COMMITMENTS : First Date? How About Hawaii? : It used to be that ‘love, honor and cherish’ preceded big-ticket vacations. Not anymore. In fact, these trips can be a good way to test a relationship.

Donna said she was surprised to discover how casually it’s done these days. The 39-year-old mother of three has been dating since she separated from her husband two years ago.

“I’ve been invited all over the place--Hawaii, Seattle, Las Vegas, San Diego, Santa Barbara--by people I’ve gone out with casually. People I’m not intimate with,” said Donna, of West Los Angeles. Like others in this story, she asked that her real name not be used.

While a weekend away has not replaced dinner and a movie, vacationing with a date is on the rise, according to anecdotal evidence from psychologists and travel experts. Increased societal acceptance allows unmarried couples to travel more openly and earlier in the relationship, they say.

Because hotel staff, travel agents and tour operators generally do not ask a couple’s marital status, they cannot quantify the increase. But based on comments clients have made and different names and addresses on checks, they have no doubt about the increase.

“It has increased dramatically in the last three to five years,” said Leslie Leonard, field manager at the Auto Club of Southern California Travel Agency in Los Angeles.

Psychologists point to changing cultural values as one contributing factor.

“The thing that kept people from doing it for the longest time was the taboo,” said Charles Webb, a psychotherapist in Beverly Hills. “There used to be all the jokes about having to sign in as Mr. and Mrs. Smith,” added Webb, who teaches “10 Ways to Attract the Opposite Sex Immediately” through the Learning Annex.

Gerald Alper, author of “The Singles Scene” (International Scholars Publications, 1994), theorizes that economic pressures have changed the way couples date and court. Amid the chaos of modern life, couples have an added reason to go away together: to enjoy each other’s company away from the distractions of jobs and friends.

So while couples may normally see each other on Saturday night and maybe once during the week, on a vacation they spend longer concentrated amounts of time together.

That, experts say, can expand the romantic possibilities and deepen their commitment.

“They can be romantic morning, noon and night--day after day,” said Alper, who has a psychotherapy practice in New York. “They can find out they really click. That can represent a breakthrough for them.”

“Sharon” and her boyfriend dated for eight months before deciding to take a one-week vacation to Hawaii. Both held down full-time jobs and attended graduate school at night. They squeezed in time for each other about twice a week.

“I thought by the third day, I’d get sick of him. But we both found out we wanted to do the same things. We were running from one activity to another,” said Sharon, 33, of Los Angeles. “The sex was better. We both said it felt like we were on a honeymoon.”

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But that kind of intense togetherness can also dramatize areas of incompatibility that can be ignored when dating twice a week.

“If you don’t get along, it can become pretty painfully apparent,” Webb said. “You may come back realizing ‘We’re not enough alike . . . we don’t have fun together.’ ”

After dating “John” for nine months, “Caroline” knew he wasn’t as outgoing as she--but the issue didn’t come up much and wasn’t a source of conflict. Then they went on a weeklong camping trip with her church group a few months ago.

“It was worse on vacation. He wanted to do he-and-I things. I wanted to be involved (in group activities),” explained Caroline, 41, of Los Angeles. “He’d go off by himself--moody and pouty. We got into big fights.”

Still, even a bad vacation can be good if it helps you realize something important about your relationship, Webb said. And if the couple decides to stay together, they may understand some of the problems that need to be worked through.

“That can be entirely positive. It is part of the learning process: How do we deal with disagreement? How do we handle needs that are sometimes conflicting?” he said.

And while part of learning about the relationship is spending time in close quarters without everyday distractions, another part is being in unfamiliar environments. Traveling produces situations beyond anyone’s control. The uncertainties of airport and car travel can be stressful.

“You get to see how the other person reacts under stress. It’s hard to keep up your very best behavior continuously even over a one-week period of time,” Webb said.

“Shirley” said she and her boyfriend arrived at the airport to find out that their flight was delayed. She was disappointed, but was appalled at her date’s reaction: “He had a tantrum . . . and was yelling at the lady at the counter. It wasn’t her fault,” said Shirley, 36, of South Bay.

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Unmarried couples in committed relationships are hardly new on the vacation scene. But Alper said he has noticed a trend toward vacationing together early in the dating process.

“What strikes me is the normalcy with which mostly men, but women too, will ask each other after the first date to go away for the weekend,” Alper said.

As a college student, Scott Brown of West Los Angeles had dated “Sally” for one week when she invited him to Hawaii for the weekend. Her family owned a travel magazine and the trip was free--air fare, condo in Maui, rental car and all.

“I was blown away by the concept. . . . The idea was overwhelming to me. It carried me along with it,” Brown said. They walked along the beach, laid by the pool and got along well, he said. “The whole thing was so new and fun.”

Vacationing in the beginning of a relationship can be exciting, said Karen Schnieder, a family therapist who teaches with Webb.

“A new person in a new environment--it’s very attractive and sexy,” she said.

But she and other experts cautioned that going away with someone you barely know can be risky.

“I would stress that you need to get to know the person through as many dates as possible before you end up halfway across the world. He could be an ax murderer,” Schnieder said. “Ask yourself: ‘How much do I really know about this person?’ ”

“Lisa” of Los Angeles thought she knew “Sam” pretty well. They met at the wedding of mutual friends and instantly clicked. They had both graduated from Ivy League universities and were professionals. After dating two months they went for a weekend in Seattle.

After they got there, he became verbally abusive. “It scared me. He totally lost his mind. I had hooked up with a psycho,” said Lisa, 33, who was forced to change hotels in the middle of the night and fly out the next morning.

It was years before she took a trip with a date again.

Said Lisa: “I think (vacationing with a date) is serious. You have to be comfortable with the relationship and the person.”