When a friendship turns sour, more than emotions get hurt

In 2014, a team at Carnegie Mellon University in Pittsburgh found that, as the amount of negativity in relationships increased for healthy women aged over 50, so did their risk of developing hypertension. Negative social interactions – incidents including excessive demands, criticism, disappointment and disagreeable exchanges – were related to a 38 per cent increased risk. 

For men, there was no link between bad relationships and high blood pressure. This is likely because women care more about, and are socialised to pay more attention to, relationships. Negative interactions can lead to inflammation, too, in both men and women. 

Jessica Chiang, a researcher at the University of California, Los Angeles, who conducted a study showing as much, has said that an accumulation of social stressors could cause physical damage, just like an actual toxin. Some of our most hurtful friendships start out good, but then became bad.

Among teens, for example, the rates of cyber aggression are 4.3 times higher between friends than between friends of friends. Or as Diane de Poitiers, the 16th-century mistress of King Henry II of France, said: 'To have a good enemy, choose a friend: he knows where to strike.' The writer Robert Greene addresses the slippery slope in his book The 48 Laws of Power (1998). Bringing friends into your professional endeavours can aid the gradual crossover from 'good' to 'bad', he warns, in part because of how we react to grand favours: Strangely enough, it is your act of kindness that unbalances everything. People want to feel they deserve their good fortune. The receipt of a favour can become oppressive: it means you have been chosen because you are a friend, not necessarily because you are deserving. There is almost a touch of condescension in the act of hiring friends that secretly afflicts them. The injury will come out slowly: a little more honesty, flashes of resentment and envy here and there, and before you know it your friendship fades.

Ah – so too much giving and 'a little more honesty' are friendship-disrupters? That conclusion, which runs counter to the ethos of total openness and unlimited generosity between friends, provides a clue as to why there are so many 'bad', 'good and bad', and 'good, then bad' friends. In his paper 'The Evolution of Reciprocal Altruism' (1971), the evolutionary biologist Robert Trivers concludes that 'each individual human is seen as possessing altruistic and cheating tendencies', where cheating means giving at least a bit less (or taking at least a bit more) than a friend would give or take from us. Good people do attract more friends (though being a high-status good person helps) Trivers goes on to explain that we have evolved to be subtle cheaters, with complex mechanisms for regulating bigger cheaters and also 'too much' altruism. He writes: In gross cheating, the cheater fails to reciprocate at all, and the altruist suffers the costs of whatever altruism he has dispensed without any compensating benefit… clearly, selection will strongly favour prompt discrimination against the gross cheater. Subtle cheating, by contrast, involves reciprocating, but always attempting to give less than one was given, or more precisely, to give less than the partner would give if the situation were reversed. *altruism involves selfless acts or undertakings that put the welfare of others before one's own*

The rewarding emotion of 'liking' someone is also a part of this psychological regulation system, and selection will favour liking those who are altruistic: good people do attract more friends (though being a high-status good person helps). But the issue is not whether we are cheaters or altruists, good or bad, but to what degree are we each of those things in different contexts and relationships. Perhaps this seesaw between cheating and altruism, which settles to a midpoint of 50/50, explains why 50 per cent keeps coming up in research on friends and relationships. Recall that half of our friendships are non-reciprocal, half of our social network consists of ambivalent relationships, and – to dip into the adjacent field of lie detection – the average person detects lies right around 50 per cent of the time. We evolved to be able to detect enough lies to not be totally swindled, but not enough to wither under the harsh truths of (white-lie-free) social interactions. Likewise, we've evolved to detect some cheating behaviours in friends, but not enough to prohibit our ability to be friends with people at all. As the seesaw wobbles, so do our friendships. Should this sound like a complicated business to you, Trivers agrees, and in fact speculates that the development of this system for regulating altruism among non-kin members is what made our brains grow so big in the Pleistocene. 

Read full article click link below