Dont u think massa is also living a life of sevika...i mean though she has so much money n authority of the house but still she doesnt has a husband n her own kids...i guess she would have been given a dharam ka path to help her sister's family n her whole life went in taking care of her sis lil ones.
The black part on her soul is cast by some past happening and once you have that u r hellbound to follow its rules...then u dont even see wats happening to others