After a lifetime in this religion and still trapped because of family, let me tell you something. BTW my parents were baptised in the 1940's and little George was never going to school in this old system.
Even if your GF manages to avoid being DF'ed (highly unlikely) and remains a pioneer (not a chance) what sort of married life can you expect? She will not want to associate with your "worldly" friends and you will definitely not want to associate with her JW friends. What happens come Christmas and birthdays? What happens when it is Regional Convention time? Does she go alone or do you tag along and go shopping while she is in the sessions? What happens if there is an emergency and one of you requires a blood transfusion?
My simple piece of advice is RUN LIKE HELL! You will thank me one day even if I'm pushing up the daisies!
George