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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A rather wet and windy evening, with rain in the north and showers elsewhere.
The 19-year-old's body was discovered in Builth Wells last month, just days after he was reported missing at the Royal Welsh Show.
The funeral has taken place of a one-year-old girl who died when a parked car rolled into a wall, which then collapsed on her.