Jessica's parents died at the scene and her sister's life support was turned off three days after the two-car collision.
Falkholt's parents, Lars, 69 and Vivian, 60, were killed instantly in the Boxing Day crash.
Vivian and Lars were instantly killed in the crash, while the sisters' bodies were pulled from the flaming wreckage of the auto by bystanders.
'We made sure Jess wasn't alone and her friends were able to be there with her, ' the relative said.
'Jess was a very private girl and while we're thankful for public thoughts and interest, we are just trying to honor what she'd want'.
The 29-year-old has spent the last 16 days following the crash in a medically induced coma in hospital and has undergone multiple surgeries. "At least she is with her family now".
'Their lives on this earth ending on a highway makes absolutely no sense'.
Friends of Home and Away's Jessica Falkholt held vigil
Vivian's younger brother, Paul Ponticello, spoke at the funeral service where he thanked people who ran to the family's aid. "Whenever asking how long it would take to drive somewhere I would suggest an average for a normal driver and then add some additional time for the Lars factor". They are together and always will be.
The other driver was Craig Anthony Whitall, a serial driving offender, who was also killed in the smash.
The family was remembered as an inseparable, radiant group.
It was reported that a auto driving on the wrong side of the road caused the collision, hitting the Falkholt family head on as they made their way home to Sydney following a short festive break.
Coroners will now try and determine whether Whitall's drug use caused the crash.