When John dated Katie, he was attracted to how book smart she was and how much she loved to learn new things. He is the first to tell you, he’s not cut out for academics and loves to play instead of learn. As someone who needed to play more, Katie was attracted to John’s outgoing and fun personality. Now, however, she finds him shallow and longs for deeper conversation. What was once attractive to Katie, now bothers her.

Researchers call this type of shift in the relationship a “fatal attraction”.  The very thing that drew you to that person becomes unattractive. Yes, it was attractive at first, but now is a problem in the relationship. Dr. Felmlee at Penn State University coined the phrase “fatal attraction” about two decades ago. She was interested in studying both the positive and negative side of traits that attract couples. She classified these traits in 3 categories: 1) Traits that were fun but now seem foolish 2) Traits that seemed fun, but now feel dominating 3) Traits that seemed spontaneous, but now feel unpredictable. The idea here is that what may have seemed positive on the front end of a relationship can become negative over the long haul.

And Dr. Felmlee has found that the shift from loving to fatal attraction can happen as fast as 6 months with some couples.

She explains possible reasons for this:

1) Couples don’t see the dark side of a trait until they are together long enough. This is why I tell people to date for a long enough period of time to see how the person reacts and acts under a number of circumstances. Negative traits can be easily masked or missed when initial attraction hits. The opposite attraction can feel like it is completing you but in the long run, may prove to be difficult to live with in a relationship.

2) When a relationship becomes overly negative, one partner begins to see even positive traits in a negative way. This idea has been confirmed by the research of John Gottman and colleagues. When there is more negative to positive in a relationship, the relationships is perceived to be overall negative. Then, the partner discounts positives in favor of the negative view.

3) Sometimes we are attracted to a negative, but opposite qualities we found tantalizing eventually  bother us-think good girls attracted to bad boys! They may be intriguing to date but terrible to marry.

4) The positive trait can become overwhelming. Think too much of a good thing, like an accommodator who is constantly trying to please you. An overly attentive person can become suffocating.

5) The opposite attraction takes its toll. You’ve had enough and want someone more compatible.

Bottom line, if you want to avoid a fatal attraction, think about the long-term effect of living with someone who has compatibility issues. Differences do attract but when it comes to values, beliefs and attitudes, we do better with similarity.

Second, if your annoyance level is going up, talk about it now. Don’t let the negativity build. See if you can negotiate a middle ground for some of your differences. This is called accommodation and  is a useful trait in relationships.

Third, build the positivity bank of your relationship when you are not in a conflict or dealing with a difference. The more positive a relationship is overall, the better you can handle differences.

Finally, discuss ways to bring the “I” to the “we” that allow you to be you, but is also considerate of the other person. In other words, modify. For example, someone who wants to be on the go constantly, can agree to stay home a few nights a week. A little self-sacrifice is beneficial to your coupling. Being in a relationship means you don’t always do what you want to do. Sometimes, you modify your behavior because you care about the other person.