The 27-year-old was due to return to Massey University on the North Shore two weeks ago to begin his third year studying business and accounting.
His father Sam Shu told the
Herald he fears his son may never fully recover from the attack.
Sam, and Rui's mum, May Zhang, say they believe their son is suffering post-traumatic stress disorder (PTSD), as he routinely "shuts all the windows and doors, and closes all the curtains due to fear".
Rui has refused medical treatment, including eye drops and antibiotics, since his release from Whangarei Hospital two days after the attack, his mum told the
On January 6, police said Rui had been walking north on Lupton Ave, near Oranga Rd about 10.30pm.
He was confronted by two men, carrying weapons and demanding he hand over his bag.
Sam said his son was told by the two men, "don't play games", before the men slammed Rui's head into the pavement and began beating him with a hammer.
Rui's eyes were cut with the screwdriver, Sam said, and his jaw, cheek, nose and eye sockets broken.
In the student's bag was a passport, bank cards, cash, two laptops and a cellphone.
Zhang said the seemingly random attack has left her son living in pain and fear "every minute, hour after hour, day and night".
She said for Rui to receive further medical treatment he is required to give permission.
"My son's mind is confused. If they can't get so-called permission from a PTSD sufferer, are they going to leave my son's facial bone fractures untreated and awful pain [for] the rest of his life?
"My son stays at home alone with his untreated face and shuts all the windows and doors and closes all the curtains due to fear, while I am working during the day," she said.
"People walk on the street and they have done nothing wrong. Then all of a sudden, they get seriously assaulted, which destroys their well-being for the rest of their lives."
Sam said his son, who enjoyed walking long distances to improve his fitness before the attack, continues to act "very strangely, he refuses to do anything".
"[His health] is very bad at home. [I've] seen many strange behaviours [since the attack], he refused to take the medication, refused to go to the hospital, refused to take any [food]."
Sam described Rui as a promising student, who had done well after the family moved to New Zealand from China in 2002, but he is worried his son's academic career may now be over.
In January, Detective Constable Alistair Todd said the assault was a "horrific, unprovoked attack by two cowards".
"The Whangarei community will not tolerate this type of disgusting behaviour," he said.
Detective Inspector Dene Begbie said police are continuing to investigate the assault.
"The victim has been understandably very shaken by what has happened to him and we continue to remain in close contact with both him and his family."
Police described the first attacker as a man in his early 20s, of solid build, and of Maori or Pacific Island descent.
The second attacker was a man of skinny build and of Maori or Pacific Island descent.