Gracie Spinks, 23, was found in a field near Staveley Road, Duckmanton, Derbyshire at around 8.40am on June 18.
Following their daughter’s death, Ms Spinks’ parents have been campaigning for Gracie’s Law, a government funding pledge to give every police force a dedicated point of contact for stalking complaints.
Speaking to Sky News, Ms Spinks’ mother Alison Heaton said: “A guy who Gracie had previously reported to the police for stalking her approached her that morning and murdered her.”
She added: “It’s just really frustrating because we’ve got no answers, it’s just dragging on, we just want some answers.”
Ms Spinks was last seen alive by her mother at 7.30am on June 18, leaving the family home in Chesterfield to drive a few miles to Blue Lodge Farm stables in Duckmanton, where she kept her horse.
She was discovered unconscious at the stables half an hour later, fatally stabbed.
The body of 35-year-old Sheffield man Michael Sellers, whom Ms Spinks’ family said was her former supervisor at a warehouse where she once worked, was found in a nearby field off Tom Lane a few hours later.
Ms Spinks’ parents said she had reported Sellers to police for stalking her, four months earlier.
Her family later discovered that a bag containing knives, an axe, a hammer and a note saying “Don’t lie” had been found close to the stables, six weeks before Ms Spinks’ death, which was then handed to police.
“This bag of weapons had been handed in on May 6 and as far as we know the police didn’t act on it and join up the dots basically from Gracie’s complaints,” her mother said.
Ms Spinks’ father, Richard Spinks, claimed that if Derbyshire Police had warned her about that find, he could have protected her.
“We wouldn’t have let her go anywhere on her own after that, so that’s the view that I’ve got: I think they let her down big time,” he said.
The Independent Office for Police Conduct (IOPC) said it was continuing to investigate prior police contact between Gracie Spinks and Derbyshire Police before her death.
Derbyshire Police said it was assisting the area coroner with their investigations into the deaths of Ms Spinks and Mr Sellers, and the case remained with the IOPC.
Meanwhile, Ms Spinks’ parents hope a candlelit vigil held on Tuesday evening to mark their daughter’s birthday will raise aware for their Gracie’s Law campaign.
“That will be her legacy,” said Mr Spinks.