"My stomach just churned when I saw that particular one," she said. "I instantly thought of Ashlee."
Wicked Campers did not respond to requests for comment.
The Advertising Standards Authority has confirmed that a complaint over the van message was being processed with a decision expected next week.
Seven complaints have been upheld in 2015 already.
The Australian company has courted controversy with the offensive messages since 2008. The company, which markets itself towards young tourists looking for a cheap ride, has outlets in the United Kingdom, North America, South Africa and South America.
Ms Edwards called on people to boycott the company.
"I think the public needs to make a stand that this is not okay and this is not condoned," she said.
The messages showed the company's "arrogant" attitude towards domestic violence, Ms Edwards said.
Since her daughter's death Ms Edwards has campaigned against domestic violence. In July last year herself and another mother, whose daughter also died from domestic violence, presented a petition to Parliament for tougher penalties for breaches of protection orders.
"I think the best thing Wicked could do is actually campaign with anti domestic violence messages," Ms Edwards said. "I think they probably get more support that way."
The photo of the van which had been spotted in central Auckland and posted to Facebook by New Zealand Women's Refuge on Monday, had gathered more than 9000 likes and 460 shares.
The refuge plans to write to the Human Rights Commission and the Advertising Standards Authority.
Complaints upheld against Wicked Campers included vans which read: "Your thighs won't touch if my head's between them." Unlike other forms of media like radio and television, there was a gap in legislation which meant removing the messages was outside of the authority's jurisdiction.
