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Think you really know your long-term partner?

 March 2019 |  Martin Fuller

"They are not the same person!" and "I don’t know where the person I married has gone!" I have heard statements along these lines through the whole of my career in family law. I have also during my time as a family lawyer come to understand that despite those statements, people do not tend to change during the stress of separation, their behaviour and attitudes can, and often do, become heightened.

I was recently reading about a behavioural study carried out by behaviour scientists Benjamin Scheibehenne, Jutta Mata, and Peter Todd. The study looked into whether or not we know our partner as well as we think we do. It interested me, so here is a brief summary.

Without going into the specifics of the study, they asked couples to rate 118 different items on a scale of 1-4 showing ‘likes’, ‘dislikes’ and ‘preferences’. Then the same people were asked to predict how their partner would rate those same 118 items.

The first group, who had been in a relationship for an average of two years scored a 42% accuracy, and the second group, who had been in a relationship for over ten years scored a 36% accuracy.  Individuals, in both groups were asked how well they thought they would actually score, and they all believed that they would be able to predict their partners ‘likes’, ‘dislikes’ and ‘preferences’ with an amazing 60% accuracy!

There are apparently several reasons why the longer the relationship, the actual level of our understanding and knowledge of our partner decreases. Often there is greater motivation to exchange information about each other in the early stages of a relationship, and that motivation reduces as time goes on. It follows therefore, that changes in a person can go unnoticed, and/or uncommunicated.

An alternative reason is that we start to trade on the time we have invested in the relationship, and believe this to be an indication that we know our long-term partner better than we do. And as such, we miss the small changes in our partner’s attitudes and preferences, especially if they change slowly over time.

Finally, there is evidence to suggest we start to tell each other ‘white lies’ to avoid full and frank conversations. The reason we do this could be to protect and fulfil an important relationship protection function which may well be understandable. However, these strategies only cause the parties to grow further apart and thereby potentially damage the relationship.

The reason I have chosen to write about this finding is that I think it can be a helpful background to anyone who is trying to save a long-term relationship. But, if you are negotiating at the end of a long-term relationship, be aware that you may not know your ex as well as you think you do!

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