Knowing whether to stay in or leave a romantic relationship is often an agonizing experience and that ambivalence can have negative consequences for health and well-being.

Now a new study offers insights into what people are deliberating about and what makes the decision so difficult, which could help therapists working with couples and stimulate further research into the decision-making process.

The study, led by U psychology professor Samantha Joel, was published in Social Psychology and Personality Science. Co-authors were Geoff MacDonald and Elizabeth Page-Gould of the University of Toronto.

“Most of the research on breakups has been predictive, trying to predict whether a couple stays together or not, but we don’t know much about the decision process — what are the specific relationship pros and cons that people are weighing out,” Joel said.

In the first phase of the study, the researchers recruited three samples of people — including people who were in the midst of trying to decide whether to break up or not — to participate in an anonymous survey.

Participants were asked open-ended questions about their specific reasons for both wanting to stay and leave a relationship.

That yielded a list of 27 different reasons for wanting to stay in a relationship and 23 reasons for wanting to leave.

The stay/leave factors were then converted into a questionnaire that was given to another group of people who were trying to decide whether to end a dating relationship or marriage. Those dating had been together for two years on average, while married participants reported relationships that averaged nine years.

In both studies, general factors considered as the individuals deliberated what to do were similar.

At the top of the stay list: emotional intimacy, investment and a sense of obligation. At the top of the leave list: issues with a partner’s personality, breach of trust and partner withdrawal.

Individuals in both dating and married situations gave similar reasons for wanting to leave a relationship.

But the researchers found significant differences in stay reasoning between the two groups.

Participants who were in a dating relationship said they were considering staying based on more positive reasons such as aspects of their partner’s personality that they like, emotional intimacy and enjoyment of the relationship. Those who were married gave more constraint reasons for staying such as investment into the relationship, family responsibilities, fear of uncertainty and logistical barriers.

And about half of the participants said they had reasons to both stay and leave, indicating ambivalence about their relationships.

“What was most interesting to me was how ambivalent people felt about their relationships. They felt really torn,” Joel said. “Breaking up can be a really difficult decision. You can look at a relationship from outside and say ‘you have some really unsolvable problems, you should break up’ but from the inside that is a really difficult thing to do and the longer you’ve been in a relationship, the harder it seems to be.”

Most people, Joel said, have standards and deal breakers about the kind of person they want to date or marry but those often go out the window when they meet someone.

“Humans fall in love for a reason,” Joel said. “From an evolutionary perspective, for our ancestors finding a partner may have been more important than finding the right partner. It might be easier to get into relationships than to get back out of them.”