Bennett - who retired in 2019 - graduated from the University of Otago in 1978 and began treating the patient, identified only as Ms E, in 2006.
The woman, more than 30 years his junior, attended appointments every three months and developed a bond with the doctor over a shared interest.
Details of the hobby were suppressed so as not to identify the victim.
Through 2015, the pair spent a "large time" indulging in the activity and would sometimes attend events together, court documents said.
On Valentine's Day 2016, E sent Bennett a photo of her on holiday, to which he remarked that she was as stunning as the vista.
When she returned to Dunedin, they spoke about their feelings for one another and agreed she should get a new GP.
However, that doctor only worked twice a week and Bennett simply filled in if she was absent.
April 2016 marked the start of a sexual relationship which went on for 27 months. During that period, E saw Bennett in a professional capacity nine times.
By mid-2018 things fell apart.
The victim disclosed details of the affair to another clinician, who later took their concerns to the Medical Council.
Further complaints were also made by E's former partner and her father.
When the council sought a response from Bennett he said they "have not engaged in any sexual conduct".
Five months later, in March 2019, he confessed that he had lied.
Bennett accepted the allegations against him - that it amounted to professional misconduct "likely to bring discredit to the profession" - prior to a full tribunal hearing.
E, in a statement, said the experience had had a profound impact upon her.
"I have recently moved to a new city, and I feel anxious about finding a new GP because the trust I have has been severely broken. I know everyone is an individual, but I now worry about dealing with doctors ... I now think there is no way I would see a male doctor," she said.
"In every realm of my life, I now find myself second-guessing men who are in power."
As well as the cancellation of his registration, Bennett was censured and ordered to pay $30,000; the latter he did not dispute.
A range of conditions imposed by the tribunal should he recommence practice were imposed outside the tribunal's power, Justice Osborne ruled.
He quashed that element of the penalty and referred the matter back to the tribunal for reconsideration.
Misconduct
July 2006: E enrols at Broadway Medical Centre and is treated by Bennett.
2015: The pair spend significant time together on a shared hobby.
February 2016: E sends the doctor a photo of her on holiday, he compliments her on her appearance. When she returns from holiday they agree she should see a different doctor, but she is still treated by Bennett.
April 2016: The sexual relationship commences, Bennett says it will take two years to leave his wife.
June 2018: E tells another doctor about her intimate relationship.
September 2018: Nurse and a doctor report Bennett to Medical Council; E's ex-partner also complains.
November 2018: The doctor tells the council there was no sexual relationship between him and his patient.
March 2019: He admits that his original response was a lie.
February 2021: Health Practitioners Disciplinary Tribunal finds professional misconduct proven and cancels doctor's registration.
