The point of conjugal is for people who literally cannot be together usually because of legal reasons - same sex couples in a country where homosexuality is illegal, or a couple who has gotten married in a country where divorce is not recognised so they literally cannot get married.
Neither the UK nor Canada has these restrictions. There was nothing to stop you and your boyfriend from living together, which you state you did, or from getting married now that your divorce is finalised - and this latter fact is probably what is going to cause you the biggest issue now. There is literally nothing stopping you from getting together in Canada, or the UK, or any other country and getting married. You are both legally able to get married now, and there are no legal reasons why you cannot. Therefore you will not qualify as conjugal partners.
Use this link to withdraw your application: http://www.cic.gc.ca/english/helpcentre/answer.asp?q=732&t=14