A Scottish court has ruled that a soldier raped a woman he met in a Dundee nightclub, after she sued him in a landmark civil action which she says proves that “justice will always be done, no matter how long and bitter the journey”.

In what is only the second ruling of its kind in recent Scottish legal history, a sheriff in Edinburgh found on Thursday that Sean Diamond, 28, a serving soldier in the British army, raped the woman after she fell asleep fully clothed on a friend’s sofa on 14 July 2015. She was awarded damages of £119,250.

Diamond, who was stationed at Leuchars at the time, was prosecuted for rape in October 2017 but a high court jury found the charges against him not proven, a controversial Scottish verdict which acquits an accused person but stops short of finding them not guilty.

Speaking to the Guardian as the judgment was made public, Ms AB said: “The last six and a half years have been so emotionally wrenching and it felt like it was never going to end. The fact that I can now read a judgment saying ‘Yes, he raped you’, in black and white and from the facts, is a closure that I never thought I would ever feel.”

In his judgment, Sheriff KJ Campbell QC praised the “quality and consistency” of Ms AB’s testimony, adding that “the consistent evidence” of her distress immediately after the attack was “difficult to reconcile with the defender’s account of consensual sexual activity”.

He said he was satisfied on the balance of probabilities – a lower standard of proof than required at a criminal court – that the defender raped the pursuer.

Ms AB was on a night out with a female friend when she met Diamond. The pair danced together and kissed before returning to the friend’s flat, along with Diamond’s male friend, between 2.30am and 3am.

The judgment found that their friends went to bed together, leaving Ms AB and Diamond in the sitting room. She fell asleep on the sofa but woke around half an hour later, on her front, being raped by Diamond. She was prevented from getting up and although she told Diamond to stop and get off her, he did not. Ms AB then lost consciousness and when she regained it, shortly after, had pain in her vagina and anus.

In a state of extreme distress, Ms AB woke up her friend, who told the men to leave and immediately called the police.

Her experience of the criminal trial was devastating: “The way you’re treated is literally like you’ve committed a crime.” She said she was “infuriated” by the not proven verdict and that “the jury were told to think about the impact their verdict would have on his military career”.

Then a family friend suggested the civil alternative. At the outset of those proceedings, in 2018, a finding was made for Ms AB because Diamond did not defend the action, but he subsequently applied to have the decree recalled, claiming he had not understood the consequences of not responding. After a number of delays, some relating to the pandemic, the hearing finally took place last September.

During the civil case, Ms AB – who attempted suicide a year after the assault and has since been diagnosed with post-traumatic stress disorder – moved to Morocco, where she now works and where she met her husband, who she describes as her “guardian angel”.

Sexual violence campaigners say they believe the availability of not proven verdicts – which leaves the accused innocent in the eyes of the law – have a disproportionate impact on rape and sexual assault cases, leading to markedly lower conviction rates. Last month the Scottish government opened a consultation on the verdict with a view to reforming it.

In October 2018, a former St Andrews University student, Miss M, successfully sued her attacker, Stephen Coxen. The court found he had raped her while she was too drunk to consent, after they met at a nightclub during freshers’ week in 2013. Coxen was previously prosecuted for rape but the verdict was not proven.

Ms AB said: “No amount of money would remove the memory and the trauma that I’ve lived with over the last six and a half years.

“Money will never replace that feeling of if he had been found guilty in the criminal trial.”

She said she would like to see reform of the justice system, not just in Scotland but across the UK, whether that is the not proven verdict, the treatment of women giving evidence, or “pathetic” sentences.

Her message to other women struggling with the justice system was simple: “Never give up. Don’t be silent, because your voice is the most powerful thing you have.”

Diamond has been approached for comment. An army spokesperson said they were aware of the judgment and that “soldiers and officers at all levels of the British army are held to the highest standards. If individuals fail to meet these standards then appropriate action is taken.”

Paying tribute to the “courage and perseverance” of Ms AB, the chief executive of Rape Crisis Scotland, Sandy Brindley, said: “This civil case – and the many criminal cases that have come before – highlight just how urgent action is to reform the justice system. We have to address the issues that make the process so unbearable for those who report sexual crimes and ensure that the system is robust.”