Angela, the Maughold register gives her address as Ramsey:
Marriage 22 Apr 1851
Thomas ELLISON Full age Bachelor Labourer Ramsey [father] Thomas Ellison, Labourer ~ and ~
Margaret CANNELL Full age Spinster Ramsey [father] John Cannell, Farmer.

Have you checked all the relevant Ramsey censuses for her age and place of birth?

Sue