The family of murder victim Suzanne Pilley has spoken of its "unbearable" pain, as a new appeal is launched to locate her body.

Speaking publicly about the case for the first time, Suzanne's sister Gail and mother Sylvia said she was "discarded" and not treated with any dignity in her death.

Suzanne, 38, was murdered by her colleague David Gilroy in May 2010.

He is believed to have killed her at her workplace in Thistle Street, Edinburgh, before transporting her body in the boot of his car to Argyll and Bute.

Gilroy was convicted of murder and jailed for life in 2012 but her remains have never been found.

Police Scotland released an interview with Gail and Sylvia just a few days after what would have been her 46th birthday.

The force has also released animated maps showing the route Gilroy's car took in order to jog people's memories from almost eight years ago.

Gail said: "Every time she's mentioned, you struggle with the fact she's not been found.

"It's hard to think about her because we just don't know where she is and that's the first thought that comes into your head when she's mentioned is just, 'where are you?'.

"So it's just extremely difficult to not know where she is and to not have laid her to rest. She wasn't treated with any dignity in her death, she was discarded."

She continued: "And we just do not know where she is. And that is just sometimes unbearable.

"But we have to move forward. I would love to be able to just give her that funeral, that dignity that every person deserves.

"But unfortunately we can't do that."

Sylvia added: "I feel and my husband feels it's as if she didn't matter and she's gone and we can't do anything about it.

"So we have to rely on the public. If they're out and about in that area - maybe dog walkers.

"We've been fortunate with the forestry workers, who have been very good.

"Any position that looks like it's been disturbed, they notify the police.

"And we're very grateful for that. Because we hope one day she will be found."

The day after killing Suzanne, Gilroy is thought to have taken her body in the boot of his Vauxhall Vectra to Argyll and Bute.

However, there are gaps in his journey between Lochgilphead and Inverary, where police believed he spent time concealing her body.

Detective superintendent Stuart Houston continues to lead the inquiry to find Suzanne.

He said: "Suzanne's family have been dignified and composed throughout their ordeal and whilst I have been involved in many difficult and traumatic cases, I cannot begin to comprehend how they must feel every day not knowing where their daughter and sister is.

"My thoughts go out to them and their bravery in agreeing to speak so that we can try to get them the answers they deserve.

"Considerable searches have been carried out in Argyll but have sadly turned up nothing.

"Whilst David Gilroy continues to maintain he is innocent, the only avenue left open at this time is a new piece of information from a member of the public."

He continued: "The gaps in Gilroy's journey, and the foliage and debris on his car tell us that he went off road somewhere near to the Rest and Be Thankful, so anyone who was in that area on May 5, 2010 and could have seen or heard something that might be the missing link in our investigation.

"Equally, I would appeal to anyone who may be walking or camping in the Argyll forest and may notice anything unusual.

"Any calls we receive will be followed up appropriately.

"Suzanne's family have seen justice done, but we now need to bring her home so she can be laid to rest."