For the last four months the pair have been rallying for support from local organisations to join the national campaign against what they say is New Zealand's biggest problem.
Next Wednesday, they will be lobbying for change in a public forum.
Donna said when she was addicted she lost her conscience and this was what was lacking in the younger generation because morals and values were not taught like they once were.
"We need to talk about it more opening and talk about the effects meth can have... it's about implanting that conscience back into our young people."
For Donna, the effects of methamphetamine drove her into the ground.
"When I was taking P I couldn't see the immediate effects because as far as I was concerned I was the only one in the room.
"The hardest part was having to deal with my daughter's questions, 'why are you doing this?'," Donna said.
It took three near-death experiences and pleas from her daughter and grandchildren to stop.
"Five years ago I was diagnosed with cancer and my P addiction was escalating the disease. I nearly died three times and, on the third time, I ended up in a coma.
"When I came out I knocked the crack on the head and for the last two years I have been clean."
Donna said she had been a different person since she became clean.
"I am far more sociable, not isolated anymore like I was. Being clean has bought me closer to my daughter and granddaughters and I get to see them all the time."
But she said there was a stigma and even though she had been clean for two years there were still people who did not trust her.
"And that I can handle because it comes with the addiction... it takes quite a while to get people's trust back but I'm still fighting."
Members of the public are invited to join the march starting at 11.30am on Wednesday at Rebel Sport on Victoria Ave to meet at Majestic Square for the forum.
Two local former P-addict mothers will share their story and local advocates including Whanganui mayor Hamish McDouall and Jay Rerekura from Nga Tai o te Awa will speak.