People who fear relationship conflicts are just as happy when they are single or in a relationship, according to new research published by the Society for Personality and Social Psychology.

"It's a well-documented finding that single people tend to be less happy compared to those in a relationship, but that may not be true for everyone. Single people also can have satisfying lives," said lead researcher Yuthika Girme, a psychology doctoral candidate at the University of Auckland in New Zealand.

In a survey of more than 4,000 New Zealand residents, a nationally representative sample, people with high "avoidance social goals" -- who try at all costs to avoid relationship disagreements and conflict -- were just as happy being single as other people were in relationships. Being single may remove some of the anxiety triggered by relationship conflicts for those individuals, the study noted. Some previous research has shown that being single usually is associated with slightly lower life satisfaction and poorer physical and psychological health.

Conversely, the study found that participants with low avoidance goals who aren't concerned about the ups and downs of a relationship were less happy when they were single. The study participants ranged in age from 18 to 94 years old with long-term relationships lasting almost 22 years on average. One-fifth of the participants were single at the time of the study. The research was published online in Social Psychological and Personality Science.

Trying too hard to avoid relationship conflicts actually may create more problems, Girme said. While high avoidance goals may help people be happier when they are single, it can have negative effects in a relationship, contributing to anxiety, loneliness, lower life satisfaction, and an unhealthy focus on negative memories, according to prior research.

With a high divorce rate, solo parenting, and many people delaying marriage to pursue career goals, the number of single people is on the rise. Single people now outnumber married adults in the United States, with more than 128 million singles representing 51 percent of the adult population.

The study also analyzed the effects of "approach social goals," where people seek to maintain relationships by enhancing intimacy and fostering growth together as partners. Study participants with high approach goals were generally more satisfied with their lives -- but also experienced the most happiness when they were in a relationship compared to those who were single. The researchers found similar results in a separate survey of 187 University of Auckland students.

"Having greater approach goals tends to have the best outcomes for people when they are in a relationship, but they also experience the most hurt and pain when they are single," Girme said.