He replied to an email saying she wanted only a friendship with a string of messages, demanding to know how she could be so certain and accusing her of spurning his love because she was immature and cowardly.

Ms. Wesko responded less often and more tersely. But over the next few years, she started experiencing severe, unexplained pain, she said, was repeatedly taken to emergency rooms. She could not locate a doctor able to treat her condition, she said, and in desperation she emailed Dr. Cahill in 2018 to ask if he knew of a good physician in Colorado, where she was living.

She eventually got a diagnosis of endometriosis that required a specific kind of surgery. Specialists were located in New York, at Lenox Hill Hospital, and Dr. Cahill arranged for them to take her case. “He jumped in and took over everything,” she said.

Her health plan would not cover procedures done out of state, so Dr. Cahill arranged for both the hospital and the surgeons to waive their fees. But he insisted that Ms. Wesko come to him for two preoperative exams.

When Ms. Wesko objected to an exam on Jan. 30, 2019, according to her lawsuit, “Dr. Cahill insisted that as her referring physician he needed to complete it. The implication was clear: She needed to meet Dr. Cahill’s demand or else she would not be able to receive the surgery that he had arranged and that she desperately needed.”

During that exam and a subsequent one, Dr. Cahill again penetrated her anally, and during the second exam, Dr. Cahill fondled her breasts, ripped open her paper gown, touched her stomach and pelvic area, and kissed her on the mouth, according to Ms. Wesko’s lawsuit.

There was no nurse or chaperone in the exam room, as is standard in most doctors’ offices, she said.