Dark days that led to the light of god The couple were then both working at Conservative Party HQ in the John Major years. But a break-up followed the next year, which apparently traumatised both young people. Indeed, it has been suggested that Adshead was set on a downward spiral of louche partying into drink and drugs. "I did think my life would progress on the normal tracks of meeting someone, marrying, having children, but that's not the path that God has led me," she said in a documentary on becoming a nun. Reflecting on photographs from her wild years, she added: "I feel like I tried most things in life that are supposed to make you happy. That journey took me down into alcoholism and drug addiction. These days, she devotes herself to worship and work with the other nuns of the Abbey of Regina Laudis in Connecticut. Here, she is effectively cut off from her previous life, communicating only by letter, and has tasks such as tending the Convent cattle and mopping chapel floors. There is no doubt that Cameron's relationship with Adshead was serious - and it's one that raises further questions about the Prime Minister's past, particularly his early years when he mixed with a wild Oxbridge set who dabbled in drugs. By all accounts, Adshead is a charming, vibrant and beautiful woman. She spent her early years in New Zealand, where her parents taught at the University of Christchurch. At 16, she returned to Britain, where she studied at £24,000-a-year Cheltenham Ladies" College before winning a place at Christchurch, Oxford. There, she met fellow undergraduate Cameron. By the spring of 1990, they were dating, and they remained together until the summer of 1991. For a time, they both worked at Conservative Central Office, before Adshead became Major's correspondence secretary. She was a leading figure in promoting the premier's pro-European policies, earning herself the nickname Miss Maastricht. It seems that she was hard hit by the end of her romance with Cameron and reportedly had to take time off work to recover. A dalliance with leading Conservative-supporting historian Andrew Roberts, a close friend of Cameron, followed. Contacted by The Daily Telegraph, he declined to comment. In early 1993, Adshead applied to work for Right-wing think tanks in Washington DC - as a newspaper diary column noted at the time, much to the disappointment of the "young swains" at Conservative Central Office, who had been "in a state of bewitchment" over the "starlet" in their midst. Even before this, it seems Ms Adshead had been thinking about religion, and how to deepen her faith. She visited a Catholic retreat in America in the early 1990s. Her schoolfriend says: "I know her faith has always been very important to her. She converted to Catholicism during the late Eighties or early Nineties. Before that she was Anglican. [Her time at the retreat] was a whole process of self analysis. Her gilded professional life ticked on. She gained an MBA from Wharton, University of Pennsylvania, before working in a senior role at the advertising firm Ogilvy and Mather - the inspiration for the Mad Men TV series. Life was as well-connected as at home - she attended charity balls in New York alongside Prince Albert of Monaco and holidayed in the exclusive Hamptons. She spoke of attending polo matches, just as in England, except "the weather is better here and the people are more attractive." Then, in 2008, she joined Alcoholics Anonymous - and that year, decided to wed herself to Christ. Her family has been supportive. Her sister is forensic psychotherapist Dr Gwen Adshead, a consultant at Broadmoor Hospital who lives in Reading. Her brother, Tom, went to the University of Cambridge, and lives in Moscow. Adshead says in the documentary: "I remember having to tell my mother, "I'm going to join the abbey," and she said: 'Yes, I can see this world has no real meaning for you any more." I looked at this place and saw women who had what I wanted. You make a decision to surrender your life to God. A monastic life, this is where the struggle is. There's no way out. You don't get to leave and go to a movie. You don't get distraction from all the human emotions. At an initiation ceremony, she swapped her fuchsia dress and pearls for a wimple, and allowed the nuns to cut off her long blonde hair. Her father, Sam, died a week after seeing her take her vows, and his ashes are scattered in the convent grounds. Adshead declined to comment when contacted by The Daily Telegraph. So what does Cameron feel when he reads of his ex-girlfriend's battle with addiction? A strange facet of the Prime Minister's persona is that his youthful years were set against a tapestry of drug and alcohol abuse. Weeks before he was due to take his O-levels at Eton College in 1982, several boys were expelled for drug use. The boys told police that a shared interest in reggae music had made them seek out dealers in west London. Back at Eton, they would roll a joint, and listen to Bob Marley records. All Saints Road, where they bought cannabis, is half a mile from the Cameron family home. Some 25 years later, a biography of the Tory leader revealed that Cameron had also been involved. It emerged that aged 15, he was questioned by headmaster Eric Anderson and when asked if he had smoked cannabis, Cameron answered unhesitatingly: "Yes." He was "gated" - confined to the school, and forced to write lines from Virgil in Latin. According to Cameron: The Rise of the New Conservative, by Francis Elliott and James Hanning, Cameron continued to use drugs throughout university. The book refers to "infrequent and moderate consumption of cannabis during his three years at Oxford," but dismisses "innuendo about alleged cocaine use" as without foundation. Publicly, despite calls to clarify whether he took cannabis or cocaine, Cameron has stuck to a now well-worn line that he is entitled to a "past that remains private." During his battle to become leader of the Conservative Party, he was forced to issue a statement admitting that a close relation had just been successfully treated for addiction to heroin. It has also been reported that his sister-in-law, Emily Sheffield, was expelled from school when drugs were found in her dormitory. Many of his oldest friends have used drugs. Josh Astor, to whom he is now related through his marriage to Samantha, was one of the boys expelled from Eton. Entering politics, Cameron apparently had private doubts about then Home Secretary Michael Howard's crackdown on "rave parties" where drug-taking was rife, according to Elliot and Hanning, "because Samantha (then his girlfriend) was attending exactly the sort of dance events Howard wanted to ban." There are other rock'n"roll connections. His sister, Clare - who introduced David and Samantha - is best friends with Jade Jagger, daughter of Mick. At the stag night for his sister's wedding in 2010, Cameron said: "Half the table was dry - either AA (Alcoholics Anonymous) or NA (Narcotics Anonymous) - and the other half were very politely having a glass of wine." One former Tory apparatchik describes the scene at Central Office when Adshead and Cameron were dating: "We worked hard, and we partied hard. Yes, there were drugs, and lots of drink. It was a hard-living, hedonistic and rather wild time. It is not clear what drugs Adshead became addicted to, nor whether she was involved in drugs when she dated Cameron. Her New Zealand friend, speaking from Christchurch where she now lives, will only say: "She has publicly admitted she was increasingly abusing alcohol and drugs. Her life in the US was a whirlwind of different engagements [and] it got out of control. She had questions, like all of us - was it worth it, the horrible feelings afterwards. She had issues to deal with. Her journey to where she is now has taken her to some interesting corners. Now, Sister John Mary passes her days serenely at the US convent. Her friend visited her there last year, and says: "She is at peace. It is where she should be. She has tasks, like tending the rose garden. When I was there, David Cameron was in the newspapers. I mentioned it to her, she simply said: 'Oh really? I didn't see that. That is the life that she has chosen. Additional reporting Gordon Rayner and Mark Hughes