This might sound too extreme for some of you, but honestly if I were Sonakshi I would break away from Suman and Pari...move out and cut contact.
Relationships are one thing, but integrity and values are also there. What's wrong is wrong, mother or not, sacrificed to make you successful or not. Sure there are responsibilities and love towards parents, but that doesn't mean you worship them blindly and overlook huge problems. There is no legit justification for Suman's greed, screaming, over-reacting, and degrading Sonakshi...so if the parent does not behave like a mature adult then Sonakshi has every right to knock some sense into her. The way Sonakshi behaves in front of Suman and Pari, like a pitiful puppy, its super disturbing to watch. She might as well be Cinderella!