My Catholic Parents Won’t Let Me Move Out

I will be graduating college in May, and my fiancé has already graduated. I have a full-time job offer for after I graduate (I am also working part-time right now), and my fiancé is working full-time. We both live with our parents right now, and we are planning to finally move out once I graduate. My parents are very strict Catholics (I am not), and essentially told me I can only move out if I am married by a Catholic priest. My fiancé and I are beyond frustrated. Any advice?