Most of us have harboured feelings of resentment after being hurt or deceived. It seems justifiable to do so. A close look at grudge-holding shows, however, that the only person who suffers is the one who holds the grudge. As Angela Buttimer, a psychotherapist in Georgia, put it, ‘When we hold on to grudges and resentment, it’s like drinking poison and expecting the other person to get sick.’

Johan Karremans at Radboud University in the Netherlands reviewed a number of studies on the relative effects of grudge-holding and forgiveness. He found the inability to forgive was inversely related to the psychological well-being of the offended, particularly in relationships with a strong commitment. John Gottman, expert in marital well-being, would agree. He notes that when couples hold on to anger and resentment, their negative feelings only intensify and separation becomes more likely.

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That’s not surprising: anger increases confrontation, and sabotages the chance of finding compromise.

Nursing a grudge – and in particular feeling anger rather than experiencing negative feelings generally – may also compromise physical health, particularly as we grow older. In an experiment, Meaghan Barlow at Concordia University found that those who were angry had higher levels of low-grade inflammation and suffered more chronic illnesses than those who felt sad, and this was particularly so among the oldest participants.

So how can you let go of your anger?

Try imagining yourself forgiving the other person – this can help us feel more in control of negativity.

Challenge your own fixed beliefs, consider alternative explanations for the other person’s behaviour, and learn to become aware of and control your own emotional state through relaxation and breathing techniques.

Writing about your experience also helps, especially if you include what you learnt from any unhappy experience.

Finally, forgiving doesn’t necessarily mean going back for more. If someone hurts or betrays you repeatedly, and if they continually refuse your requests to talk things through, you may need to step back from that relationship. Forgiving means letting go of negative feelings only. Once anger goes, trust the logic that remains.

The Daily Telegraph