But the 28-year-old says she cannot easily access transfusions from Waitematā District Health Board because some doctors believe she is deliberately bleeding herself to cause the severe anaemia.
She believes their suspicions stem from a conflicting diagnosis of factitious disorder - previously called Munchausen syndrome - where a person makes up a physical or mental illness to get sympathy and special attention.
Three other psychiatrists have concluded Aston does not have factitious disorder or any psychiatric illness.
Forensic psychiatrist Dr Caleb Armstrong has warned Waitematā DHB that the "extraordinary situation" represents a "grave risk of disservice and perhaps danger to the patient".
"It's her life at stake," he told the Herald. "Currently they don't transfuse her. She has a low haemoglobin because they accuse her of doing all sorts of things to herself and they've got no evidence of that."
Another independent psychiatrist, Dr Kjell Granrud, found Aston had no mental health disorders and that "...until it has been proven that she is producing factitious results or self-harming, that diagnosis should be put to rest".
Aston's EDS diagnosis, explaining years of seemingly unrelated medical illnesses and injuries that effectively ended her sporting career, was made by New Zealand's only EDS specialist, rheumatologist Dr Fraser Burling, and two New Zealand geneticists.
Burling said Aston's dilemma was typical of many EDS patients, who were often misunderstood and undiagnosed. "Patients are being denied care that they need."
Aston is one of four women spoken to by the Herald who have formal diagnoses of EDS, but who have either been diagnosed with or suggested as having factitious disorder or personality disorder traits by the same doctor, who the Herald has agreed not to name, 'Doctor A'.
He assessed Aston's history as "suspicious" for factitious disorder with a "differential (likely) diagnosis" of somatic symptom disorder, where an extreme focus on physical symptoms such as pain or fatigue cause major emotional distress and problems functioning.
Aston and a second woman, Nichola Smith, each complained to the Health and Disability Commissioner about Doctor A's assessments of them but were told it was not the HDC's role to intervene in a disputed diagnosis.
A third woman, Dr Rachel Palmer, complained to a disability advocate and says Doctor A tried to assess her without properly introducing himself as a psychiatrist.
Now the three women are having difficulty getting the treatment they believe they urgently need, which they claim is a direct ramification of their psychiatric evaluations.
A fourth EDS patient seen by Doctor A - Georgie Ferris - lost 20kg and was planning her funeral before doctors finally treated her.
All four patients say the assessments by Doctor A were unwanted and breached their rights under the Code of Health and Disability Services Consumers' Rights.
Complicating Aston's condition is gastroparesis, where the stomach cannot empty itself, rendering her unable to digest food.
She is surviving on 400 calories of liquid each day because of the pain, choking and vomiting when she eats.
Aston, who also has severe reflux disease and constipation, has been advised to get a surgically inserted feeding tube that would bypass her stomach to deliver formula through a vein directly to her intestines.
But every specialist the Auckland woman is referred to has yet to insert a tube.
Auckland DHB said it could not comment on any of the patient cases but that its high calibre doctors treated based on the best available evidence, in a patients' best interests, avoiding "inappropriate clinical interventions that risk causing unnecessary harm".
Waitematā DHB, which has previously stated it holds grave concerns for Aston's wellbeing, said it had gone to considerable lengths to ensure the highest quality care had been delivered to her.
Aston's parents David and Pam have written a letter to Waitematā DHB, saying; "We believe (Doctor A's) incorrect diagnosis of factitious disorder has caused significant damage to Stephanie's life and her ability to access safe, both physical and psychological, care in the medical system".
The pair told the Herald; "We've both grown up respecting doctors and believing them but it just seems in this situation that if they don't know what's wrong, she must be lying. It's appalling."
International EDS expert Dr Heidi Collins said psychiatric misdiagnoses were common among EDS patients and the challenge was understanding why some psychiatrists were "absolutely unwilling to see or accept an underlying physical issue".
Since publication, Auckland District Health Board has responded to the Herald's series about EDS and factitious disorder published this week. An Auckland DHB spokeswoman said the stories seemed to have singled out Doctor A, which was not a fair representation of the diagnostic process.
"Although we can't comment on the specifics of individual cases, these sorts of diagnoses are not determined by an individual clinician in isolation but form part of a diagnostic process and comprehensive medical assessment that includes input from a number of specialist clinicians."
The series
Today: Stephanie Aston Tomorrow: Nichola Smith Wednesday: Georgie Ferris Thursday: Dr Rachel Palmer Friday: Tracey Jourdain