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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Wintry showers to continue through the weekend and warnings of gales
Exclusive figures given to ITV Cymru Wales show a steep rise in the number of people seeking advice for steroid use.
Cold, breezy and generally cloudy at first with further wintry outbreaks on the hills