“If I can’t have her, no one can”

The mother of four said Hall and McPhail had a typical teenage relationship at first, but her daughter realized he was controlling her.

Mrs Trussler believed her daughter was a victim of domestic violence, although she was under 16 at the time and her ex-partner had caused emotional distress.

He changed her social media passwords and made her believe he could hack into her accounts and threatened to harm himself.

Her mother said Holly feels sorry for McPhail and doesn’t know how to end the relationship.

Mrs Trussler said: “It got to the point where she really made up her mind but was still trying to switch off, mainly because he wouldn’t let her. He was obsessed with her for a long time.

“He didn’t like her going out. He didn’t want her to go out with friends. He needed to know where she was at all times, even if she was just at home.

“He wanted to know what she was doing. He changed her passwords on all her social media, so she was really upset about that because she couldn’t get any of it.’

Mrs Trussler said Holly told her MacPhail had once warned her that “if he couldn’t have her, no one could”.

The grieving mother said: “We didn’t know what he meant.”