This is same Sonakshi who had come to Ishwari house as a nutritionist. I know things are not that naive and innocent but for Sonakshi Dev is gud son and a gud father.
She has accepted that Dev will take gud care of Suhana as father and probably she will have to accept him as a co parent and thats it.
She is not interested in ne other bond with Dev bcoz she knows, Sonakshi doesnt fit in the makeup of Dixit family and Dev still doesnt have courage to stand for her.
She has forgiven Dev for their past as Soha's father but not as her companion. She has accepted her mistakes but she knows they are still standing at the same point.
Ishwari wont accept Sonakshi and Sonakshi is not ready for another heart break.
She as an mature adult has made things smooth for n Dev's co inhabitance but no as any emotional involvement.
Sonakshi has probably realised after so much negativitu around her and Soha she has met Dev that all this is affecting Soha the most and probably her peace of mind also.
Ishwari is Dev's mother, she is the most important person in his life and other person is Soha. She herself doesnt want to be a competitor for Ishwari.
She has not accepted Dev as her companion at all.
This is really mature approach on Sonakshi's part