Brother-in-law Nick Margison said Mardie had severed her spine in the fall.
Tragically she is now a paraplegic and has zero chance of ever walking again, he said.
Her next four months will be spent in a spinal unit before returning home in a wheelchair.
A trust fund has been set up so Ben can take time off work to look after their four kids and to find a rental without stairs that will allow wheelchair access to be built.
Margison appealed to Lythes former team-mates at the Vodafone Warriors, the Mount Albert Lions and the Glenora Bears to contribute to the fund.
Former Vodafone Warriors Awen Guttenbeil is working with the old boys network to generate support for Warrior No 79 Lythe, who made five NRL appearances for the club in 2000, represented New Zealand Residents and played extensively on the Auckland club scene and in the old Bartercard Cup competition.
Vodafone Warriors chief executive Wayne Scurrah said the club would donate $5000 towards the fund.
Our hearts go out to Ben, Mardie and their family at this terrible time, he said.
Donations can be made via internet banking to:
Account name: Lythe
Account No: 38-9007-0327920-01
List your name in reference field