Looking for lasting love? It's not all looks and laughs

An analysis by online dating website eHarmony shows what people find attractive in a possible partner may not be the same qualities that will make the relationship successful, which is a lesson learned by those who have been married.

For example single women aged under 45 were 13 times more likely than married women under 45 to stress the importance of feeling passion and desire toward their partners.

Single women aged over 45 were nearly twice as likely to stress the importance of love, compared to their married peers who were more likely to cite companionship.

"We know what we are attracted to. It is very easy to see. But the challenges of finding someone attractive can cloud over what is very important across the long haul," said Gian Gonzaga, a senior director of research and development at the California-based company.

eHarmony compared the responses of 598,000 users registered on its website, some who had been previously married and some never married, about the qualities sought in a potential partner.

Never-married singles tended to put more emphasis on physical appearance, passion and personality in a partner, while formerly married singles focused on a person's beliefs, values, emotional intimacy and skills at resolving conflict, as well as sexual compatibility.

"The study showed that singles tend to focus on the emotional aspects of a relationship and don't focus as much on the skills and requirements that are necessary to make a long-term relationship stronger," said Gonzaga.

An accompanying survey of 2,020 adults in the United States by Opinion Research Corporation for eHarmony, which was founded in 2000 and is available in Canada, Australia and Britain, supported the findings, according to Gonzaga.

"It's great to be passionate about your partner but if you're not compatible, if youH don't share important underlying characteristics, you are going to bump into problems down the road," Gonzaga added.

Valentine's Day is among the busiest periods of the year for online dating sites, according to Greg Blatt, the CEO of the online dating website of Match.com, which operates in 24 countries and 15 languages.

"The need for love and companionship is always there but I think there are certain periods in the calendar where people who aren't in a relationship and want to be feel it especially profoundly," he said.