Holding a grudge is bad for your mind, body and soul, but how easy is it to move on?

Stylist.co.uk contributor Aimee Meade speaks to professor of psychology Thomas Plante, forgiveness expert Megan Feldman-Bettencourt, and Ruth d’Andilly-Clune, an inspirational woman who has found the power to forgive her father for his abusive alcoholism.

Growing up, we’re told to 'forgive and forget'. Some things are easy to forgive; a best friend borrowing and subsequently losing your new jacket, your flatmate using (but not replacing) the last bit of milk. Others are unforgettable. So, how do we forgive and forget - and should we?

“Remembering is not a problem - it's how you remember,” says Megan Feldman-Bettencourt, journalist and author of the book Triumph of the Heart: Forgiveness in an Unforgiving World. “When you hold a grudge, every time you think about that person or the situation, your brain is flooded with stress chemicals like adrenaline and norepinephrine.

“Over time, those chemicals put you at risk of depression and anxiety, and they inhibit your frontal lobe's ability to solve problems,” she explains. “The stress caused by chronic anger also elevates risk for high blood pressure and heart problems.”

This is something that Ruth d’Andilly-Clune, a 25-year-old web designer from West London, knows all too well.

Three years ago her world was turned upside down when her parents’ 13-year marriage ended, and as a consequence her father, a loving man who only ever drank at Christmas, suddenly became an abusive alcoholic.

“I no longer recognised him as my Dad, the person I grew up with,” she tells me. “He was verbally abusive towards me, he would put me down and… would say things about my Mum I shouldn’t hear… [It got] to a point where I thought it would be better to not have him in my life at all. It was too painful.”

Despite her encouragement, Ruth’s father refused to get help. Her mental health suffered and eventually, she was prescribed anti-depressants. “I didn’t want to get out of bed. I didn’t want to do anything. I sat in my own little world, I wouldn’t talk to anybody. I was upset all the time. It made my relationships with people who were trying to love and help me difficult - I was so angry.”

“It is not for the other person, it is for you”: how to master the art of forgiveness