The man who strangled a teenager to death for rejecting his sexual advances is "pure evil", the victim's grieving mother has said.
Lewis Haines was jailed for 23 years at Swansea Crown Crown Court on Friday for killing Lily Sullivan, following a night out in Wales last year.
Speaking after Haines was sent to prison, Lily's mother Anna said the "actual truth" of what happened on the night she was killed "will haunt me for the rest of my life".
Haines, a 31-year-old father-of-one met Lily, 18, at a nightclub in Pembroke, southwest Wales, on 16 December.
The pair kissed and later went to a nearby alleyway together where they became more intimate.
Lily was later found face down and topless in the Mill Pond, a two-mile-long freshwater reservoir near the town.
After carrying out the murder, Haines walked past Anna's car as she waited at a garage to pick up her daughter from her night out.
Anna said Haines "looked me straight in the eyes knowing what he had done".
"The events of the night Lily died go over in my mind constantly and I wake up in the night picturing Lily in the water wondering if she knew what was happening, if she was scared," she said after the sentencing.
"I wish I had stopped Lily going out that night. I picture the man responsible for her death when I saw him at the garage, and I wish I had confronted him.
"Knowing I was that close to her, I wish I'd got out of my car and walked. I always wonder if I could have saved her."
Haines confessed to murdering Lily but denied sexual misconduct.
But after a trial of facts, judge Paul Thomas QC concluded Haines had killed the teenager after she rebuffed his sexual advances.
The court was told how Lily made a call to her mother at around 2.47am, telling her she would be with her soon.
The call was cut off mid-sentence and the prosecution said that it believed that “Lily was attacked at that point”.
"He looked me straight in the eyes knowing what he had done," Ms Sullivan added. "I feel now that this was Lily trying to tell me something and reaching out to me, which is unbearable.
"I question what happened when her phone went dead when I was speaking to her, what I could have done differently so she'd still be alive.
"I play that whole night over and over in my head - it's like being tortured thinking just one decision could have changed the whole night."
She added: "These thoughts never leave me and I can't stop thinking about it. I have to live with the fact that I now never know what really happened to Lily that night.
"I suspect the actual truth will haunt me for the rest of my life."
Sentencing Haines, judge Paul Thomas QC said: "You strangled her face-to-face, she must have been terrified.
"An 18-year-old girl all alone in the dark with a powerful man,” he continued. “She was entirely at your mercy and you, Lewis Haines, showed her none.
"You were entirely thinking about your own self-preservation."
He said Lily’s death had caused "devastation to many".
