Anne-Marie Hirdman is said to have been repeatedly attacked by Police Constable Fraser Ross.
The 41-year-old is alleged to have repeatedly grabbed her, pinned her to the ground and placed his hand over her mouth.
On another occasion it’s claimed he pushed her and repeatedly headbutted her.
And he is also said to have tried to choke her after forcing her to the ground, placing his hand over her mouth and and digging his knee into her body.
A court heard on Tuesday that she refused to leave their bedroom after one alleged assault at his hands.
And she is said to have kept the abuse hidden for so long because she loved the officer and did not want him losing his job or his parents finding out.
Ross is currently on trial at Hamilton Sheriff Court, where he has pled not guilty to five charges stemming from his relationship with Miss Hirdman.
And he faces two charges of behaving in an abusive way towards her, one between 2013 and March 2019, and one between April and August 2019.
On Tuesday one of the couple’s friends, Donna Alexander, gave evidence.
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The 38-year-old said she had known PC Ross for about 17 years as her husband was friends with him, and became close to Miss Hirdman as a result.
She said the couples were supposed to be going on a night out in October 2017 but that Miss Hirdman cancelled the night out via WhatsApp, before they talked on the phone.
Mrs Alexander explained: “She just kept saying, ‘I don’t want to involve you’.
“I said, ‘oh tell me, it won’t jeopardise your relationship, if that’s what you’re worried about’, and then she went on to tell me what had happened.
“She said they had got into an argument and it had just escalated from there.
“She said there was screaming and shouting and he’s been trying to stop her from screaming and shouting.
“She said he restrained her on the floor to try and get her to quieten down.
“She was distraught, upset, struggling to speak – there was lots of crying.
“I think it had happened the night before and spilled into the next day.
“She told me she was in pain and she sent me pictures of marks on her body.
“I was trying to talk her into going to the police and going to the hospital.
“I sent her information for Women’s Aid, domestic abuse, to get in contact.
“She said she’d also done that previously.
“She didn’t want Fraser to lose his job and she was worried about Fraser’s mum and dad finding out.
“She was in so much pain.
“She said she was locked in the room, basically – she just wanted to hide away.’
Mrs Alexander said Miss Hirdman “eventually” went to hospital after she had been “nagging her” to go.
And she said she received a phone call from her in August 2019 to say that Ross had been arrested in connection with the alleged domestic abuse.
She explained: “She was hysterical, she just wouldn’t stop crying and was out of breath.
“She was just distraught, I could barely understand her.
“I went straight to her.
“She was a wreck. She just looked so fragile, she looked terrible.
“There was marks all over her arms.
“There was cushions all over the floor, broken ornaments, broken photo frames.
“She said they had got into an argument after a night out with another couple and it had turned violent.
“She showed me her legs, her legs had bruises all over them.”
Ross has denied the allegations and the trial, before Sheriff Ross Macfarlane QC, continues.