Bell was convicted of three murders and one charge of attempted murder and is serving a life sentence at Paremoremo - New Zealand's toughest prison. He is not eligible for parole until 2031.
Darnell Tupe, who was Bell's getaway driver but took off early, was sentenced to 12 years' jail for manslaughter and aggravated robbery.
A memorial service will be held at the RSA today at 11am. It will be attended by victims' families, Sensible Sentencing Trust director Garth McVicar and the Crown Solicitor for Auckland, Simon Moore SC, who was the prosecutor for the trial.
But Ms Couch has decided not to go.
"It's pretty hard for her at this time of year," said Mr McVicar.
"It's very hard for her to go back to that place. She finds it all too tough."
Ms Couch told the Listener that while she was almost destroyed physically, she still had a strong will and was looking to her future.
"It's a conscious choice: You can either be miserable or get off your arse," she said.
Mrs Hobson's husband, Tai, will attend, as he has every December 8 since her death.
"I'll be up there. It's a thing that's passed, I feel okay," he said. "It's a thing that we keep going to every year, whether it's a big [anniversary] or a small one. It's a chance to have contact with the families of the other victims. It's comforting."
Mr Hobson said the time since his wife's death had gone "very quickly".
"We want to move on. But we still want to remember, and we'll still keep going back."
Mr McVicar said it was disappointing Ms Couch was still fighting the legal system to get compensation for the permanent brain and physical injuries she suffered in the attack.
An Appeal Court judge described Bell as "callous and brutal".
"Bell separated his victims and coldly beat them to death or near death, each in their turn. The horror and terror experienced by each of these four innocent people passes all imagining ... The calculated wickedness and evil inherent in these crimes cannot be over-stated."
Ms Couch later sought damages from the Department of Corrections for failing to exercise "reasonable care" in Bell's supervision. He was on parole for an earlier aggravated robbery when he committed the murders.
The Court of Appeal struck out the High Court action, but that was overturned by the Supreme Court - which gave Ms Couch the go-ahead to sue the department.
Ms Couch and her supporters, including lawyer Brian Henry and Mr McVicar, were hoping the case would go to trial in March.
SERVING TIME
William Bell: Convicted of attempted murder, aggravated robbery and three counts of murder. Sentenced to life in prison with a minimum non-parole period of 30 years. Eligible for parole December 2031.
Darnell Tupe: Convicted of manslaughter and aggravated robbery. Sentenced to 12 years' with a seven-year minimum non-parole period. Parole declined October 2011.
