(CNN) -

Toronto Mayor Rob Ford asked for forgiveness Monday, his first day back to work following a two-month leave of absence for substance abuse treatment.

"To the people of this great city, I want to offer a public apology," said the embattled mayor at a news conference. "I used poor judgment and I take full responsibility for my actions."

In May, Ford announced that he'd be taking a break after reports of a video that allegedly showed him smoking crack cocaine surfaced -- apparently the final setback in a year full of them for a man who said Monday that he was in "complete denial" about his substance abuse.

"When I look back on some of the things I said and some of the things I did when I was using, I am ashamed, embarrassed, and humiliated," he said.

The Canadian mayor's public unraveling began in May 2013 when cell phone video surfaced that appeared to show Ford smoking crack cocaine. He denied any wrongdoing and defiantly brushed aside calls for his resignation, even after the city council stripped him of most of his power.

Ford pledged to quit drinking and adopt a healthy lifestyle, but after another embarrassing video appeared on social media in January -- one in which he incoherently mocked the city's police chief -- Ford admitted to suffering a setback.

Though he offered apologies Monday to "every single person who was hurt by (his) words and actions," one thing Ford did not offer was his resignation.

In fact, the mayor -- who is seeking another term -- doubled down.

"I look forward to serving you for many, many more years" he said.