A.Mary left home to start an independent life with a view to realising how much her family meant to her.
B.Not until Mary had left home to start an independent life did she realise how much her family meant to her.
C.To realise how much her family meant to her, Mary decided to leave home to start an independent life.
D.Only when Mary realised how much her family meant to her did she leave home to start an independent life.