Jeannette Clements says her daughter is innocent of murder, claiming that she struck her husband accidentally as he rode his motorbike alongside her car at night.
Nicole Reyes, who has two children living with their grandparents in Rumney in Cardiff, could face up to 30 years in prison if found guilty of her husband's murder.
"Sometimes you just feel as though you can't even cope - and it's the same with my daughter," says Jeanette.
"She has her good days and bad days, but she's getting more bad days now as time goes on, because we didn't expect it to go on for this length of time."
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Three men have been arrested after a stabbing this morning in Cardiff. Two people are in a stable condition in hospital.
Gruffydd Wyn Roberts, a 22-year-old from Amlwch on Anglesey, received a standing ovation as he performed Nessun Dorma.
A second man who tried to help at the incident was also taken to hospital