In 1881 120 Ifield Road is at RG11/47 50/29:
several households, in case any of the surnames ring a bell:
Robert Pellat, and wife Charlotte
Elizabeth Askey, and sister Edith (born Belgium!) (navy connection)
Sophia Lynes, a widow, and her daughter Hannah
Lewis and Sarah Fines, and a visitor, Valentine Carnell.
None of the families have domestics with them but some of their neighbours have boarders (there are a couple at 124), so she could have been working in the area and renting a room at 120.
Did Elizabeth have:
elder sisters/brothers also unaccounted for in 1881?
aunts/uncles on either side currently unaccounted for in 1881?
Are there witnesses on the marriage certificate whose names you don't recognise? (perhaps a coworker or friend or someone else who also lived at 120 Ifield Road). If she was working in 1881 as a live-in domestic then someone who wasn't very sure of her age or birthplace might have given the information to the census taker.