Gilliams has been jailed for the attack that happened on Christmas day in 2018.
Henry said the special holiday will never be the same again.
She told how she began the day with her children, Taylor, nine, Lili, four and Charlie, three, opening presents she had left under the tree at their home in Swansea, South Wales.
"The children couldn't wait to see if Santa had been on Christmas morning. When they saw their presents the kids excitedly opened them," she recalled.
"Mark just sat on the sofa with a bottle of beer in his hand. As the morning passed I began preparing lunch and I watched Mark getting drunker and drunker.
"The kids asked him to play with them but he just grunted and kept drinking instead.
"Then he got up and said he was going to the shops and came back with a bottle of whisky in his hand. Soon he had swigged most of it down too.
"I tried to reason with him and ask him to stop because it was Christmas Day but it was useless."
Henry added her family had visited during the day but left because of Gilliams's abusive behaviour.
"My family left but told me they were coming back for me and the kids because they were so worried about Mark's behaviour," she said.
"As soon as they left he started insulting me with abusive names.
"Then he punched me in the face so hard that it caused me to blackout."
A concerned neighbour who had heard the commotion had called the police at 12.45am on Boxing Day.
"Mark is out of our lives forever. I never want to set eyes on him again."
- Australscope
If you're in danger now:
• Phone the police on 111 or ask neighbours of friends to ring for you. • Run outside and head for where there are other people. • Scream for help so that your neighbours can hear you. • Take the children with you. • Don't stop to get anything else. • If you are being abused, remember it's not your fault. Violence is never okay
Where to go for help or more information:
• Women's Refuge: Free national crisis line operates 24/7 - 0800 refuge or 0800 733 843 www.womensrefuge.org.nz • Shine, free national helpline 9am- 11pm every day - 0508 744 633 www.2shine.org.nz • It's Not Ok: Information line 0800 456 450 www.areyouok.org.nz • Shakti: Providing specialist cultural services for African, Asian and middle eastern women and their children. Crisis line 24/7 0800 742 584 • Ministry of Justice: www.justice.govt.nz/family-justice/domestic-violence • National Network of Stopping Violence: www.nnsvs.org.nz • White Ribbon: Aiming to eliminate men's violence towards women, focusing this year on sexual violence and the issue of consent. www.whiteribbon.org.nz
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