There is a lot at stake this week for Sophie Blake, a 52-year-old mother to a young adult, who was diagnosed with stage four cancer in May 2023.
As MPs vote on whether to change the law to allow assisted dying, Sophie tells Sky News of the day her life changed.
"One night I woke up and as I turned I felt a sensation of something in my breast actually move, and it was deep," she says, speaking from her home in Brighton.
"Something fluidy, a very odd sensation. I woke up and made a doctor's appointment."
Sophie underwent an ultrasound followed by a biopsy before she was taken to a room in the clinic and offered water.
"They said, 'a hundred percent, we believe you have breast cancer'."
But it was the phone call with her mother that made it feel real.
"My mum had been waiting at home. She phoned me and said 'How is it darling?' and I said 'I've got breast cancer,' and it was just that moment of having to say it out loud for the first time and that's when that part of my life suddenly changed."
Sophie says terminal cancers can leave patients dreading the thought of suffering at the end of their lives.
"What I don't want to be is in pain," she says. "If I am facing an earlier death than I wanted then I want to be able to take control at the end."
Assisted dying, she believes, gives her control: "It's an insurance policy to have that there."
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On Friday, the government is set to debate the issue before voting on it. Sophie hopes they'll back the proposal.
"It should be my choice to be able to have a compassionate death," she says.
There has been much debate about the bill since details about how it would work were published earlier this month.
On Friday, former prime minister Gordon Brown became the latest senior political figure to share his opinion on the matter, coming out as against the legalisation of assisted dying, based on his experience of his own daughter's death.
Disability rights advocate Lucy Webster warns that for people like Sophie to have that choice, others could face pressure to die.
"All around the world, if you look at places where the bill has been introduced, they've been broadened and broadened and broadened," she tells Sky News.
Lucy is referring to countries like Canada and Netherlands, where eligibility for assisted deaths have widened since laws allowing it were first passed.
Lucy, who is a wheelchair user and requires a lot of care, says society still sees disabled people as burdens which places them at particular risk.
"I don't know a single disabled person who has not at some point had a stranger come up to us and say, 'if I were you, I'd kill myself'," she says.
The assisted dying bill, she says, reinforces the view that disabled lives aren't worth living.
"I've definitely had doctors and healthcare professionals assume that my quality of life is inherently worse than other people's. That's a horrible assumption to be faced with when [for example] you've just gone to get antibiotics for a chest infection. There are some really deep-seated medical views on disability that are wrong."
Under the plans, a person would need to be terminally ill and in the final six months of their life, and would have to take the fatal drugs themselves.
Among the safeguards are that two independent doctors must confirm a patient is eligible for assisted dying and that a High Court judge must give their approval. But the bill does not make clear if that is a rubber-stamping exercise or if judges will have to investigate cases including risks of coercion.
Julian Hughes, honorary professor at Bristol Medical School, says there's a very big question about whether courts have the room to take on such a task.
"At the moment in the family division I understand there are 19 judges and they supply 19,000 hours of court hearing in a year, but you'd have to have an extra 34,000," he explains.
"We shouldn't fool ourselves and think that there wouldn't be some families who would be interested in getting the inheritance rather than spending the inheritance on care for their elderly family members. We could quickly become a society in which suicide becomes normalised."
(c) Sky News 2024: Mum diagnosed with cancer tells of the day her life changed ahead of assisted dying vote