The Windsor man accused of murdering Lesley Watterworth took the stand at his own murder trial Tuesday and confessed to killing his girlfriend.

John Pierre, 49, has pleaded not guilty to second-degree murder in connection to the death of 42-year-old Watterworth on Nov. 1, 2016.

For the past few weeks, the jury has heard from the crown’s witnesses, including friends, people who encountered Pierre in the hours and days following Watterworth’s death, as well as police officers.

But in court on Tuesday, Pierre told a version of events not yet heard by the jury, starting with his childhood. Pierre told court he was molested as he made his way through the foster system.

He also admitted to a lifetime of drug use, starting in Grade 6. Pierre said he does drugs every day, including crack cocaine, crystal meth, Gravol, heroin, OxyContin and alcohol.

“I’m a slave to it. I always go back to it,” he said.

Pierre told court he had known Lesley Watterworth when they were younger, but reconnected later in life, in 2015.

Pierre explains a situation where he and Watterworth got into an argument, before he admitted to stabbing her.

"I exploded. I exploded like a can of coke...I just grabbed a knife and went crazy," Pierre said. He said they both collapsed to the floor.

“I was in shock… I had the knife and was on top of her. She wasn’t moving,” he said. “I had ringing in my ears… I was looking at her and crying.”

Pierre then said he went to the Beer Store, then to his friend Willie’s, and after that, two restaurants. He then went to the riverfront where he says he considered jumping in, but instead went to the casino knowing he’d be arrested after using a credit card with no money on it.

“I didn’t want to kill her. No. I don’t think I wanted to hurt her.” Pierre told the court, as defence lawyer Ken marley held up a picture of Pierre the night he was arrested by police. “It’s a man I never want to be again.”

Earlier this week, Dr. Elena Tugaleva, the examining pathologist, outlined the extent of the victim’s injuries — including the fatal blow blamed for her death.

Dr. Tugaleva testified a 15 centimetre-deep gash in Watterworth’s back that hit her liver and lungs was the fatal injury. Blood in Watterworth’s lungs was also given as a contributing factor in her death.

In all, the pathologist identified 69 “sharp forced injuries” including 22 stab wounds, 44 slices or cuts and three injuries caused by a thrusting, slicing action.

During cross-examination, crown attorney Shelley McGuire suggested Pierre's judgment was not clouded by drugs and alcohol and we was well aware of the crime he committed.

"She fought for her life in that room, didn't she?" McGuire asked Pierre.

"Yes," he responded. "I know."

Pierre didn't call 9-1-1 after the incident. When asked why, Pierre told the court "I don't know."

He then said he loved Watterworth, and still loves her to this day.

With files from CTV's Stefanie Masotti