PRINCE Harry was 12 when his mother, Princess Diana, died in 1997. In a Telegraph interview last week, he revealed that for the next 20 years, his only way of coping with such catastrophic loss was to block all feelings and thoughts about her death.

For children – who have limited experience of life and living and who struggle with the very concept of death – this is a common defence strategy. While the fact of the death is not denied, the emotions in response to it are shut down to the extent that the child lives as if the dead parent has been "disappeared", or even, when the child is profoundly traumatised, never existed at all.

In effect, they wipe the slate clean, leaving a big, empty space. While such defences are not too damaging in the very short term (especially when the child is not given permission or helped to express their grief by the adults around him), ultimately, the denial of such powerful feelings impacts adversely on the child’s development and mental health.

Often the damage doesn’t become apparent until adolescence or adulthood and by then – 10 or 20 years after the event – the grief has become so deeply buried and misshapen by the heavy weight of denial, it can be difficult for the person (and those close to them), to make sense of its manifestations. More often than not, its calling card is depression, anger, anxiety, self-harm or, in more extreme cases, a form of personality disorder.

Prince Harry’s only clue that he was drowning in a turbulent sea of unexpressed grief, was that his life (and relationships) had become totally chaotic by the time he was in his late 20s. By then, his brother Prince William and sister-in-law Kate had become so concerned, they told him he had to get help to learn how to talk about his feelings. He did and now feels much better for it. No doubt, he wishes he’d sought help sooner.

It's not easy to talk about loss, grief, shame, guilt, rage, fear. These are the big guns in our emotional arsenal and they have a habit of rattling us to the core. Much better to keep them under lock and key, only allowing them to explode every now and then (making sure to put them back in the box as soon as possible). Powerful emotions can make us feel vulnerable and out of control, so we expend all our energy on trying to disown them or keeping them cordoned off in the "Do Not Enter" section of our mind. The best way of disowning feelings is just denial, “No, no I’m not angry, just a bit perplexed about why you said that”, or, the hardy perennial of denial. “I’m fine thanks. Just fine.”

In a culture that adulates perfection and material success and tantalises us with the prospect of happiness on demand, there is little room for the awkwardness and complexity of real emotions. They take time to recognise and understand.

They appear, at first, not to make any sense at all. They squat in our consciousness like the neighbour from hell or the embarrassing relative who has a knack of showing us up in the harshest of lights.

Real feelings – particularly those spawned from traumatic experiences or events – are rough and raw and powerful. If we are unable to acknowledge and talk about them, we risk harming not just our mental and physical health, but our relationships, our families, careers, finances, everything.

Feelings and how we react to them, are one of the key, load-bearing cornerstones of our identity. If we pretend they're not really there or morph them into something we think others will like, our foundations become really wobbly.

In my experience, both professionally and personally, it is not the feelings themselves that cause people to become depressed, anxious or troubled. It's their resistance to those feelings, which opens up the gateway to a catalogue of misery: mental illness, loneliness, a life not fully lived.

Whether we like it or not, Emotions R Us (or, at least, a very big chunk of us). If we are prepared to get to know them, they can be a loyal, intelligent and steadfast mentor. Turn your back on them and you're never quite sure what will happen next.