Is there a possibility that they/she returned to England? (If so, it would narrow the search years in Canada.) After a quick search, I’m not finding them in Canada. What makes you believe that they sailed to North America, please?
1861 Leeds, Yorkshire, England Census
Martha Holbrook, age 53, widow, born Knaresboro, Yorkshire, England
Occupation: Housekeeper. Inmate, Leeds Workhouse