The parents of a young woman who took her life at The Gap want "catfishing" to be criminalised after their "bubbly, fun-loving" daughter became a victim of a faked romance they believe was orchestrated by her friend.

An inquest into the tragic death of 20-year-old Glenhaven woman Renae Marsden in August 2013 is set to examine the act of luring someone into a relationship using a fictional online persona, with her parents Teresa and Mark hoping the person behind the sinister hoax will be held responsible.

Renae Marsden, 20, is believed to have taken her life after falling victim to a 'catfishing' plot.

"There is no closure for us until we determine the facts surrounding her disappearance, and this won't be resolved until [the friend] decides or is forced to tell the truth, Mr Marsden said on the eve of a five-day inquiry to be held at the NSW Coroners Court in Lidcombe.

"Ultimately we would like to see the perpetrator charged, and that the coroner recommends the laws surrounding catfishing are tightened to make it a criminal offence."