The mother of Clare Bernal has questioned why she had to struggle to get "straight answers to simple questions" about her daughter's death.
Mrs Bernal said she had faced a "long, hard struggle"
Patricia Bernal, from East Sussex, said it was also "simply beyond belief" that her daughter's killer was released on bail after only eight days in prison.
In a statement she said: "It has been a long hard struggle to get to today."
Ms Bernal was shot dead by her former boyfriend Michael Pech at Harvey Nichols store in Knightsbridge in 2005.
Pech then killed himself.
Mrs Bernal said: "As a parent, it was important to me to find out exactly what happened in the lead-up to my daughter losing her life.
"But I have to question, why do bereaved families have to struggle so hard to be heard? "I know that mistakes will always be made, but why should families have to take on the police and the courts to expose failings in the system to secure justice?
"Bereaved families have something to say and questions to ask. We want straight answers to simple questions."
'Changes and improvements'
She added: "It is vital that people realise just how weak the system is in protecting young women like Clare from violence.
"I had hoped the coroner's findings would lead to changes and improvements that will help protect future victims and their families from stalkers."
On Thursday a coroner ruled that the killing of Ms Bernal at the store by her ex-boyfriend "could not have been reasonably foreseen".
But Westminster coroner Dr Paul Knapman said the Metropolitan Police had made a number of mistakes in handling the case.
These included charging Pech with a less serious offence than the one recommended by prosecutors after he was first arrested, and failing to fill in relevant forms.