Polish model Rubik was born in Rzeszów, Poland. In 1988 she and her family moved to Greece. They later moved to Canada and to Umtata, South Africa. Among the schools she attended was one in Częstochowa, Poland. Rubik was introduced to modeling while attending a British high school in Paris. She wanted to finish her schooling before officially becoming a model, and so only worked on school holidays. Her mother, father and sister still reside in Poland.
Rubik and her longtime boyfriend, Serbian model Sasha Knezevic, became engaged just before Christmas 2010 in Vienna.They married on 16 July 2011 in Deia Majorca. She wore an Emilio Pucci wedding dress.