Stephanie Forster did everything right.

She obtained a restraining order, changed her phone number and moved three times in six months. She once found an Apple AirTag in her car so she asked police to search the vehicle for other trackers.

But none of it helped, her sister and a women's advocate say.

Forster, 39, was shot and killed outside her Coquitlam, B.C., home on Dec. 8, and while the police investigation is ongoing, her estranged husband, who died days later, was the main suspect.

"Stalking is homicide in slow motion," Angela Marie MacDougall, executive director of Battered Women Support Services, said in an interview.

She said stalking is "a very serious and largely misunderstood part of an abusive relationship."

Tracking technology, like AirTags, gives stalkers even more access to already vulnerable women, and her group is urging police to take all forms of harassment seriously, MacDougall said.

"In our work, we've seen that police are very resistant to wanting to take action on stalking. AirTags specifically are quite alarming (because) there's very little, frankly, that survivors can do."

Forster's friends and family gather Saturday for her celebration of life in her hometown of Selkirk, Man.

MacDougall said Forster's experience of violence leading to her death is a case study in all of the ways that abusive partners can be lethal, but it also highlights the limitations of law enforcement.

Two days after her death, Forster's estranged husband, Gianluigi Derossi, shot himself while his vehicle was pulled over by police. He died later in hospital.

"Derossi was identified as a suspect in the homicide, prior to his death," the Integrated Homicide Investigation Team, or IHIT, said in an email. "Though Derossi is now deceased, the file remains open, and IHIT continues to investigate."

Stephanie's sister, Rhiann Forster, is calling for more police accountability.

"This was foreseeable and preventable, you know, he escalated in a textbook fashion."

She said Coquitlam police, the Metro Vancouver force where her sister complained about the harassment, "dropped the ball hard, really hard."

"This is somebody who knew what she was supposed to do, and she did every single thing and they still failed her. To me, that really paints a picture of how profoundly the system is broken."

Forster said the family has been working to piece together the events that led to Stephanie's death.

"She didn't give any one person the full story because she was so embarrassed," Forster explained.

The couple met in the fall of 2021, and they were married by December. It wasn't until February that her sister discovered his true identity, Forster said.

Derossi had been convicted as a serial romance fraudster under the name Reza Moeinian.

Stephanie Forster called the police and Derossi was arrested. He was eventually released under conditions, including that he can't contact his wife, her sister said.

Still, Stephanie faced months of harassment.

She sought an annulment on the grounds that Derossi had falsely represented himself, then later asked for a divorce, which he was contesting, Forster said.

Battered Women Support Services helped her obtain a protection order. but Derossi breached that at least six times, MacDougall said.

"We have seen increasingly over the years, and particularly the last three years, an erosion of the enforcement side of the protection orders," she said.

While many respect protection orders, those who are the most abusive tend to violate them, MacDougall said.

"A portion will engage in what is called criminal harassment and stalking behaviours, and those, in terms of research, evidence, and in Stephanie Forster's case, are the ones that hit all the notes with respect to the potential for lethal violence."

The homicide team said it was aware that a warrant had been issued for Derossi's arrest, before his death, related to the breached protection order.

"Enforcement of protection orders is handled by the detachment of jurisdiction and IHIT is not in a position to comment on their protocols," it said.

Coquitlam RCMP said it could not comment on the case because IHIT was leading the investigation.

A Statistics Canada report from last October shows police-reported family violence increased for the fifth consecutive year in 2021, with a total of 127,082 victims. On average, every six days a woman is killed by an intimate partner, the agency said.

It found criminal harassment was 10 per cent higher in 2021 than in the two years before, while indecent and harassing communications increased by 29 per cent since 2019.

Rhiannon Wong, technology safety project manager at Women's Shelters Canada, said digital forms of intimate partner violence also began increasing in 2020, as technology became more integrated because of the pandemic.

"Perpetrators are using technology as another tool for their old behaviours of power and control, abuse and violence," she said.

In August 2021, the BC Society of Transition Houses surveyed anti-violence programs across the province. Out of 137 respondents, 89 per cent said women they worked with had disclosed some form of technology-facilitated abuse.

"Harassment has been ranked the most popular form of tech-related violence that increased significantly during the COVID-19 pandemic," the report said.

Stephanie Forster suspected there might be another AirTag in her car, like the one she had previously found.

Rhiann Forster said her sister had an appointment with RCMP to search for tracking devices on Dec. 9, the day after she was killed.

Forster said her family was initially divided on their feelings about Derossi's death and the fact that he would never stand trial.

"But I think generally speaking, we were all just relieved that he wasn't a danger to anyone else and that he wouldn't get away with it," she said.

Forster said she hopes there is some way to ensure her sister's death has meaning for other victims.

She said she believes there should be mandatory criminal record checks of a potential spouse before a marriage licence is granted and reform of the way police handle breaches of protection orders.

"They need to change how they're enforcing those policies, because they're not doing anything to protect women."