Mark William Allen, 31, was given a 12-year sentence at Leeds Crown Court for sustained abuse of the girl dating back to the early 2000s.
Allen, who was living in Thirsk, North Yorkshire, at the time of his arrest, was found guilty after a trial in which his victim, who is now 25-year-old, was forced to give evidence.
Granted lifelong anonymity, she told the Express: “My life has been so badly affected that I’m not sure I can ever move on from this but at least I can rest better at night knowing he isn’t able to harm any other children.
“I struggle day to day with severe anxiety disorder, depression and PTSD-like symptoms.
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“I have been heavily medicated for some years due to the significant trauma I’ve sustained.”
She said Allen was a family friend whom she met when she was just six and he began acting in a ‘overly friendly’ manner which escalated over time, showering her with gifts and complements.
By the time she was 11, she said he was coercing her into sexual abuse which lasted for the next three years. However, he would swear her to silence, telling her he was in love with her and that he would be in trouble if anyone found out.
His victim added: “As a child I found it difficult to keep secrets from my family, knowing it was wrong but also wanting to protect the man that had by then become my ‘boyfriend’.
“It sounds crazy now as an adult but it was such a difficult situation for a young girl to comprehend that I didn’t really realise the ramifications of his actions until I was much older.”
It was only when she was told in 2013 that Allen was jailed for other sexual offences that she was able to build up the courage to tell the police of her own experiences.
Speaking after Allen’s conviction, Det Insp Vanessa Rolfe of the Wakefield District Child Safeguarding Team, said: “Allen committed some horrendous abuse against a very young and vulnerable victim and we are pleased this has been reflected in the substantial sentence he has received at court.
“He clearly poses a real danger to children and I hope his victim will take some comfort that he has been brought to justice and is answering for his crimes against her.”