After getting married, they moved out of their parents' home and set up their own household.
Tips
usage
Three common senses: (1) leaving the family home, (2) starting your own business or practice, (3) founding a new school in academia or the arts. Context decides which.
memory
门户 literally = 'door and household.' To 自立 (self-establish) your own 门户 is to hang your own shingle.