Earlier this year, Gloria Taylor, 64, won a court-approved exemption from the laws when a judge ruled Canada's ban on physician-assisted suicide infringes on the rights of disabled people.
The announcement of her death came on Friday from the B.C. Civil Liberties Association, which took up her court fight.
"Gloria's death was sudden and unexpected," said a news release from the group.
"The cause of death was a severe infection resulting from a perforated colon. Due to the acute nature and brief course of her illness from the infection, Gloria did not need to seek the assistance of a physician to end her life."
The release went on to say that Taylor died quickly and peacefully in hospital, surrounded by family.
"She was spared from the prolonged death from ALS that she dreaded and which inspired her participation in the lawsuit."
Taylor was among the plaintiffs in the landmark case that prompted Judge Lynn Smith to rule the ban on assisted suicide violates two sections of the Charter of Rights covering the right to equality and the right to life, liberty and security of the person.
She said the law must allow for doctor-assisted suicide in cases where patients have a serious illness or disability and are experiencing intolerable suffering.
Such patients must ask for the help, must be free of coercion and cannot be clinically depressed, the ruling noted.
Smith also granted an immediate exemption to the law, allowing Taylor, one of the women who brought the lawsuit, to die with a doctor's help.
The federal government launched an appeal in August and also asked the B.C. Appeal Court to overturn Taylor's exemption, but Justice Jo-Ann Prowse rejected that request.
In a written decision, Prowse said revoking Taylor's exemption would cause irreparable harm to Taylor, something that would outweigh the federal government's interests.
Prowse acknowledged Taylor has become a symbol in the right-to-die case, but the judge said that Taylor is also a person who shouldn't be sacrificed for the "greater good.''
The B.C. Supreme Court decision was suspended for one year to give Parliament time to fix the law, but the Appeal Court has extended that suspension until after it renders its decision.
The appeal is expected to be heard next spring.
Taylor's mother, Anne Fomenoff, said in a statement issued by the civil liberties association that her daughter will be missed.
"But we are grateful that Gloria was given the solace of knowing that she had a choice about how and when she would die. . . Gloria was able to live her final days free from the fear that she would be sentenced to suffer cruelly in a failing body."
Fomenoff said she was immensely proud of her "feisty and determined daughter."
The B.C. court fight was widely believed to be just the first step in a fight that will likely end at the Supreme Court of Canada.
Another B.C. woman, Sue Rodriguez, was the first to challenge Canada's laws against assisted suicide. In 1994, the Supreme Court of Canada ruled against her.
But the B.C. Civil Liberties Association has argued much has changed since then. Jurisdictions around the world, including in Oregon, the Netherlands and Belgium, have laws in place to allow assisted suicide that includes safeguards so vulnerable people are protected, the group said.
But this summer's attempt to reopen the debate was as vigorously opposed by opponents as the Rodriguez case was.
"We're saddened to hear of her death and had hoped she would enjoy a longer life and we remain convinced that she was mistaken in pursuing this litigation as a way to handle her situation," Dr. Will Johnston, of the Euthanasia Prevention Coalition BC., said Thursday.
Grace Pastine, litigation director for the civil liberties association, called Taylor a "heroic woman."
"Even as her own body failed her, she fought for all Canadians to have choice and dignity at the end of life.
"She spent the last days of her life tirelessly advocating to change the law."
Pastine said the lawsuit that Taylor was involved with will continue.