I was born into one of the world’s most notorious religious cults

‘By the time I was 10 years old, he had pretty much gone from being on the frontline into hiding,’ she says.

‘The narrative for us was he needed to be able to listen to God’s voice, but the reality is police were investigating certain homes and communities and investigating child abuse allegations.’

While David Berg was investigated for these crimes, he was never charged or convicted with any offences before his death.

Berg’s theory, and the foundations of the cult’s birth in 1968, was that ‘a generation protected from the influences of groupthink would be protected from being moulded into society’s view of what life should be and would be able to think for themselves’.

But Petra, now 41, tells Metro.co.uk about the ‘regular indoctrination’ she and her family experienced.

‘Every song had lyrics that had their messaging in it saying “God’s the truth” and we would read letters or words from the cult leader,’ she says.

‘Every bit of propaganda, everything we read, every bit of literature, comic books, music, story books, was influenced by him and was often his narration, his voice, his prophecy and instruction.

‘So by the time you’re saying “oh I don’t know about this” or “this doesn’t feel right”, you already have the counter argument in your brain, because it’s been there from birth.’

As Petra says in her book, Begin With You, she and her family ‘traded one groupthink for another’ and it’s why, as a mental health practitioner today, she can’t stress enough the importance of independent thinking.

In Petra’s memoir she recalls events from life inside the cult, plus the ‘double-life’ she started leading outside of it, both of which left her with complex PTSD.

In her teens and early twenties she lived what she describes as a ‘hedonistic’ lifestyle of excessive drinking and drug use, getting arrested, experiencing extreme sexual violence and attempting to take her own life at 26, after leaving the cult at 22 due to falling pregnant with her first child.

Petra says: ‘What’s interesting is seeing the parallels between cult life and how we survive toxic behaviour. What I see in the corporate world is people doing similar things like giving up their own values in favour of survival and getting paid.’

Falling pregnant with her son gave her the final push she needed to leave.

‘People often ask, “how did you escape?” As if it were a prison or walls or a compound and it’s nothing like that when it’s these sorts of communities. It’s more the prison of your mind,’ she says.

‘You could leave at any time, and they would tell you so, but then in the messaging you would receive daily, it was people who left, God punished, so if bad things happened to them it’s because they weren’t listening, which would make people afraid of leaving’.

She adds: ‘For me and my siblings, we didn’t go to school, we didn’t have an education, we thought the world was going to end imminently, so everything out there was painted as other or evil.

‘It was a big leap in your mind to betray it and for many people they were ostracised by their own parents and support networks and would struggle in a big way once they left that safety net.’

When she left at 22, Petra moved in with her partner in London and cut contact with her family for a while. Transitioning to life outside the cult was difficult, exacerbating her depression and alcohol addiction.

‘You have the shock of “what this isn’t how other people think? My parents lied to me?” and then there’s depression and anger before you get to that acceptance,’ Petra says.

In time, she learnt healthy coping mechanisms to better manage her trauma. Now, as a full-qualified mental health practitioner, Petra wants the people who read her book to understand our ‘wellbeing, focus, plans or tactics can change over time’.

‘What I needed in the early days was to get sober and to learn how to be honest and to understand my feelings and emotions,’ she says. ‘These days, it’s movement and exercise, it’s having good people around me.’

Fostering independent thinking is also vital, she says.

‘I think expression in the right way is key for your mental health,’ says Petra.

‘It can be deeply personal like art which can help you – journaling, writing – all these things can help you go “oh that’s what I think”.

Looking to the future, Petra believes that her experience with groupthink and mental health can be translated into other areas of life.

At one keynote event, a young woman said: ‘I’m waking up at 5am, I’m journaling, meditating, exercising, taking cold showers and I’m more anxious than I’ve ever been’.

‘I was thinking “no wonder”,’ says Petra. ‘We all think that we have to “do wellbeing” and achieve it by following all these people that seem to have these perfect Instagram lives and I just think the challenge to ourselves is to, even in this space, learn to think for ourselves, check our influences and then allow that to evolve over time.’

With that in mind, Petra said one of the most important things to do to preserve your mental health is to be ‘radically honest’ and ‘challenge your own bullsh*t’.

‘That doesn’t just mean speaking to a therapist, it could, but it means being radically honest with yourself,’ she says.

‘For example, asking yourself “what do I really want?”. If fear of other people’s opinions didn’t matter, how would I be living my life and I think more people are starting to ask some of these questions in a post pandemic world.’

She also stresses that while it’s important not to ‘minimise trauma’ it’s important not to get stuck there.

‘Trauma, big T little T, it doesn’t matter,’ she says. ‘It’s less about the thing and more about how it’s affecting your body and mind.

‘We don’t want to minimise trauma and mental illness, but we also don’t want to get stuck there, because I’ve been in that stuck place where I was like “well I’ve got depression, if you grew up like me you’d have it to” and I would surround myself with people that would feed that information back to me.

‘No matter what context you’re in, whether it’s a toxic relationship or a work environment that’s affecting your physical or mental health, so many people just say, “well that’s the way the world is”.

‘So I challenge people to begin with themselves and think what is one small thing that is within my control.

‘I used to listen to a one minute guided meditation, that was the only thing in my control. I challenge people to experiment with wellbeing tools and being honest and learning about themselves and what can work for them.’