I am stretched out on a mattress in front of a log fire, tears running down my face, crying for my sister, as my mother strokes my hair and whispers into my ear. I have cried many times for my sister – she died when we were children, and I am now 56 – but I’ve never been soothed like this before. It feels amazing.

The woman touching my face and shoulders with such love is not my actual mother, who is hundreds of miles away. I am in the oak-panelled great hall of a Victorian country mansion beside the River Usk in the Brecon Beacons in Wales, and my carer is Turiya Hanover, co-founder of the Path of Love retreats.

I’m not afraid of either vulnerability or honesty, I announced proudly at the first group session of this week-long retreat. I’m sorted. I then went from being the most confident in the room to the most terrified in the space of – what? – 90 minutes. The first session of this “journey” took place in the great hall where our lives were now based. We were asked to say something about ourselves and what we intended to commit to during the seven-day spirituality-based personal development workshop. I was more interested in saying something about what I would not commit to. I had my story worked out; I knew what mattered, what I thought was negotiable, what I thought was not. I commit to hear your stories, I said generously to my fellow travellers. I still thought that was what I was here to do.

But then the ground below me, which had seemed so firm and solid, turned to quicksand. Suddenly I was terrified. I ran from the room, keen to catch the first train home. Turiya came to find me: she held my hand, and she wiped away my tears. I told her I was done with grieving, but realised Clare’s death is the gateway to everything else in my story: to dig as deep as was needed, I would have to go through the tunnel of mourning yet again. She looked at me, and I knew she understood.

Turiya asked me to go back into the room with her. She’d stay by my side. By now the rest of the group – we were 40-strong – were doing a meditation, lying on mattresses on the floor in the dimly lit hall. I lay on a mattress, and she lay next to me, wiping my tear-coursed face, whispering in my ear. And that was when I knew that I was being looked after the way I should have been looked after, the way no bereaved child can be looked after because whatever has devastated the child’s life has inevitably devastated the parents’ lives, and so I had grieved as so many children grieve – alone.

All the same, I wanted to leave. I wrote as much in my workbook that night, in the space that said: “What is your intention for tomorrow?” So how did I end up not only staying, but loving it? The transformation, like all transformations, started with me.

I hadn’t entirely thought Path of Love would be a breeze. I’d signed a form agreeing to the rules, and they were scary. We would be in silence, except during therapy; there was no alcohol, no drugs, no cigarettes, no mobiles, no contact with the outside world, no sex, and no sloping off to hide in your room.

In effect, we were children again – in a nursery with very clear boundaries. If we talked, we were scolded; if we were late, the whole group had to wait. It was tough love, but also an extraordinary opportunity. Because we were being given the chance, as Rafia Morgan, Turiya’s Path of Love co-founder, put it, to “go down into the basement of our souls and dig out the shit”. There was no possibility of anyone not having any in their basement: the only question was, who would be brave enough to take a shovel, to open a door and clean it out?

Our base became our small group of 10, which we were encouraged to think of as our “lifeboat”, sat in horseshoe formation, two therapists alongside, and four or five observers behind a table. This wasn’t a place of storytelling. We were given guidance about what to look for down in the basement, as it were, after which we came forward and stood before the entire group of about 15, and told them what we had found. At times there were raised voices, shouting, wailing, sobbing.

“From the outside we look as though we’re in an asylum,” Turiya whispered in my ear. But by this stage we all knew that contained in our madness was our sanity, and that in our weakness lay our strength.

Here’s why: because from those basement excavations came the chance to say things we had never said, sometimes to people long dead. We have all been wronged at some point in the past: ignored, overlooked, abandoned, bereaved. Some of us have been used; some of us have been abused. We carry these scars in our deepest crevices, and usually we don’t get the chance to properly feel the grief, the anger, the injustice, the pain. The Path of Love process gave us that chance, in a clever and natural way. I felt myself being healed, and around me others were being healed as well – often from pain far more complicated than my own.

Every day of the seven days brought new revelations about ourselves, new discoveries, newly exposed layers of our personalities. Every time I thought I was done, I quickly realised there was even more to find out. We’d been told not to bring any novels or work of any kind: there would be more than enough to do dealing with what we had inside ourselves. I couldn’t imagine that was true, and had come armed with a novel. Not only did it go unread, but I found myself waking at three or four in the morning and realising there was no possibility of returning to sleep: these were hours I needed, to go through the huge changes taking place inside myself.

Path of Love is an immersive experience – it takes you completely out of your normal self. Hanover and Morgan, the co-founders, met in the Osho International Centre in Pune, India, and the retreat they’ve devised owes something to the spirituality of the controversial so-called “Orange People” led by the late spiritual guru Osho (formerly known as Rajneesh). They’ve taken with them the principles of honest self-evaluation and added in an at-times brutal model of group psychotherapy. However scary it is, though (and it sometimes was very scary), I always felt well supported and looked-after: all the leaders on the retreat are trained, experienced psychotherapists. I had a sense of being “in with the psychotherapy in-crowd”, with professionals who saw the Path of Love as the toughest personal challenge around.

Each evening brought a meditation, and these drew on a broad array of thinkers including professor and author Brené Brown on vulnerability and the late Catholic priest John O’Donohue on Celtic tradition. Here are some things there were a lot of on my Path of Love adventure: dancing, blindfolds, mattresses, badges. More dancing, cushions, soup, fruit. Yet more dancing (I lost 3lb), Kleenex, water bottles, reminders to go for a pee. We had checked out of our ordinary lives for a whole week, with no to-do list except, perhaps, a list that had only one item on it: me, and my psychological health.

In the final hours of the retreat, we were allowed to speak recreationally again and we realised that while we knew things about each other that no one else outside the group had ever known, there were many ordinary things that we didn’t know. Usually we meet people from the outside in – on this retreat, we had got to know people from the inside out. The rest of the group, aged from their mid-20s to their mid-60s, were from across the globe. They were actors and accountants, bankers and yoga teachers. At around £2,300 (with accommodation and food), Path of Love isn’t cheap – but there’s a fund to help the less-well-off to attend.

In the end, having been so keen to leave, I could hardly tear myself away. I realised that to move on and give life our best shot, we need to start by looking not outside ourselves but inside. Into the deepest crevices, the darkest caves and the sheerest drops of our beings. Path of Love gave me the chance to do that. Three months on, I continue to feel changed, and lightened, and validated by the experience.

For more information, see pathretreats.com