But let's begin with babies.

The pioneering mid-20th century Viennese psychoanalyst Melanie Klein,

famously drew attention to something very dramatic that happens in the minds of babies during feeding sessions with their mothers.

When feeding goes well, the baby is blissfully happy and sees mummy as 'good'.

But if, for whatever reason, the feeding process is difficult, then the baby can't grasp that it's dealing with the same person it liked a lot only a few hours or minutes ago.

It's simply filled with rage and hatred.

In order to tolerate this, the baby splits off from the actual mother a second 'bad' version, whom it deems to be a separate, hateful individual, responsible for deliberately frustrating its wishes,

and in the process, protecting the image of the good mother in its mind.

There are, in this baby's mind, two people at large, one entirely good, the other entirely bad.

Gradually, if things go well, they'll follows a long and difficult process by which the child integrates these two different people,

and comes sadly but realistically, to grasp that there is no ideal, 'perfect' mummy,

just one person who is usually lovely but can also be cross, busy, tired, who can make mistakes, and be very interested in other people.

It may be a very long time since we were being fed as babies.

But the tendency to 'split' those close to us is always there; for we don't ever fully outgrow our childhood selves.

In adult life, we may fall deeply in love and split off an ideal version of someone, in whom we see no imperfections and whom we adore without limit.

Yet we may suddenly and violently turn against the partner, or a celebrity or a politician, someone whose good qualities once impressed us,

the moment we discover the slightest thing that disturbs or frustrates us in them.

We may conclude that they cannot really be good, since they have made us suffer, and that the only logical verdict we believe is that they must then be appalling.

We could find it extremely hard to accept that the same person might be very nice and good in some ways and strikingly disappointing in others.

The bad version can appear to destroy the good one, though, of course, in fact these are really just different and connected aspects of one complex person.

It is a huge psychological achievement to accept other humans in their bewildering mixture of good and bad,

capacity to assist us and to frustrate us, kindness and meanness,

and to see that, far more than we're inclined to imagine in our furious or ecstatic moments,

most people belong in that slightly sobering, slightly hopeful grey area that goes by the term 'good enough.'

To cope with the conflict between hope and reality,

our culture should teach us good integration skills, prompting us to accept with a little more grace what is imperfect in ourselves, and then, by extension, in other people.

We should be gently reminded that no one we can love will ever satisfy us completely, but that this is never a reason to hate them either.

We should move away from the naivety and cruelty of splitting people into the camps of the awful and the wondrous,

to the mature wisdom of integrating them into the large collective of the 'good enough'.

Our collection of essays, "Why You Will Marry the Wrong Person" proposes that we don't need perfection to be happy, as long as we enter our relationships in the right spirit.

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