Charlotte Charles shares memories of her son Harry Dunn, speaking to ITV News Anglia's Graham Stothard
The mother of teenager Harry Dunn said family had to remind her to brush her teeth and take a bath after "going numb" following the death of her son.
Charlotte Charles admitted she "drank more than I should have done" in an attempt to dull the pain she felt when the 19-year-old was killed in August 2019.
As Anne Sacoolas, a 45-year-old US citizen, pleaded guilty to causing death by careless driving, Mr Dunn's mother said she would finally be able to start grieving properly.
Sacoolas had diplomatic immunity asserted on her behalf by the US government following the crash near RAF Croughton, and was able to leave the UK 19 days later. It took three years for her to appear in court charged with causing the death of Harry.
Thinking back to the aftermath of the crash, Ms Charles said: "It takes more strength than you can ever begin to imagine - and you don't see that you're going to be able to do it in the beginning.
"Friends and family are reminding you: 'clean your teeth, let's run you a bath'. They bathe you because you literally haven't got the strength to do it and it's the last thing on your mind.
"You're numb, you're in shock. You don't want to eat and drink.
"I drank more than I should have done because it used to numb the pain. But it quickly becomes apparent that it doesn't, not forever, and it's not worth it. But it's everything you can do to cope."
Harry would have been 22 in March and his family had hoped to see him get married and have children - something he had told them he wanted.
'There's always something missing', says Charlotte Charles
Ms Charles said family was "number one on his list".
"He's just very sadly, sorely missed. He would have grown into a family man with a lot of important values," she added.
The motorbike-mad teenager, described by his family as a petrol head, began saving for his first bike at the age of 14. He bought it just before he turned 16 and, when he passed his test on his birthday, was straight out on it.
His parents followed him for 20 miles on his first ride out and they were always confident he was safe.
But on 27 August 2019, Anne Sacoolas pulled out of RAF Croughton in Northamptonshire on the wrong side of the road. She hit Harry as he rode along the B4031 and, despite attempts to revive him, he died.
In December 2019, the Crown Prosecution Service authorised Northamptonshire Police to charge her with causing death by dangerous driving.
But despite protracted negotiations, the US authorities repeatedly refused to extradite Sacoolas so she could face trial.
The breakthrough finally came last month, three years after Harry's death, when Sacoolas appeared before a UK court for the first time. She joined the hearing at Westminster Magistrates' Court via video link from the US.
An inquest has still not been heard and Ms Charles said she had lots of questions remaining.
"I still don't know the final details of what happened that night," his mum said. "I believe it was a female who rang 999 - one of the witnesses. It wasn't Sacoolas. So I need to be able to go and thank those people for doing all that they did.
"There's so much we still need to know that keeps you awake at night."
Harry's family have always insisted they were not interested in seeing Sacoolas punished but, over the last three years, their need to see justice done has grown.
Calling what they had gone through over the last three years "barbaric and beyond despicable", Ms Charles said it could have all been avoided if she had remained in the UK.
"We wouldn't be here now," she said. "We would have been long down the road and being able to celebrate Harry - and we will get to do that hopefully soon."
With the court case finally over, she now plans to focus on her memories of her "petrol head" son
"It's painful. It's painful knowing what when you get on a plane or get in the car to go somewhere, someone's missing. But I'm glad I've got the memories."
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