Delisle, a naval officer stationed in Halifax, pleaded guilty in Nova Scotia provincial court earlier this month to selling military secrets to Russia.
Court documents obtained by CBC News paint a picture of heartbroken man struggling with a failed marriage.
"The love of my life since high school stuck it in my heart. It was, it was really, really, really, really hard," Delisle told an RCMP interrogator.
"I needed to be spontaneous. Raising kids for 20 years and going through what I went through with my wife, I was, I went through a period where I just decided I want to do it," he said.
In total, the interrogation lasted close to four hours. After hours of talk, RCMP Sgt. Jim Moffat told the spy the police had copies of his emails to Russia.
"There is no doubt, no doubt on my mind Jeff, that you did transmit classified documents illegally to Russia," said Moffat.
"I am so dead. I, everyone, my wife that I loved for so long, killed me. Killed me," said Delisle. "So I committed professional suicide."
Delisle told Moffat he didn't do it for the $3,000 a month.
The exhibits show he had access not only to military secrets, but also files ranging from the Canadian Security Intelligence Service and RCMP to the Privy Council Office.
CSIS said it doesn't know what data on international operations Delisle smuggled out on a thumb drive.
The intelligence agency said the leaks have caused severe and irreparable damage to Canadian interests.
Walked into Russian Embassy with offer
Delisle's career as a spy started in 2007 when he walked into the Russian Embassy in Ottawa, the day he said his wife cheated, and offered to sell secrets to that country's military intelligence agency, known as GRU.
He was then posted to the security unit HMCS Trinity, an intelligence facility at the naval dockyard in Halifax. While there he worked on a system called the Stone Ghost linking the "Five Eyes" allies: the United States, Britain, Australia, New Zealand and Canada.
Information presented at Delisle's bail hearing detailed how he would browse for material on the secure computer at Trinity, save it in the notepad feature, then transfer it to a floppy disc and thumb drive.
Delisle pleaded guilty, but he has not yet been sentenced. His sentencing hearing is set for two days in early January.