Women were made to believe their only purpose in life was to become mothers.
In past they had no role in family matters or public life.
Still many are limited from participation in public life or family affairs.
They would get rewarded for producing male heir. It decided their status. In royal families also it earned them special titles.
Hence this over protective and possessive behaviour towards sons.
There is culture of putting males on a pedestal and nearly worshipping them through festivals like Raksha Bandhan, Bhai Dooj, Karwa Chauth etc. Be it as brother or husband, male is deified.
This explains near blind defense of men in family, supporting them no matter what.
Women are not encouraged to have their own life, different goals and interests. They base life on marriage and kids (specifically sons). Motherhood has been celebrated too much and defined as "standing by" child no matter what, forgiving child always, taking on the world for sake of child etc. Expectations from mothers are twisted. Maa maan jayegi is a constant refrain.
Sakshi and Suchitra have nothing in their life if kids are subtracted. Suchitra still does some social work and worship. But Sakshi has no life at all. She was just in party circuit earlier!
Sakshi married Rajnath but I assume she was given more power only after bearing a male heir. He was probably the only one she got to truly call her own. Otherwise she was an orphan and Rajnath doesn't seem like a caring family man either.
I suspect Sakshi has been hyper ever since Shaurya started growing up and becoming independent - increasingly distant from her. The rape case made her more possessive as she did not want to lose her son to jail or noose.
Sakshi has seen worst side of life on roads hence her brain ticks more than anyone else. And she is possessive of Shaurya.
Suchitra is typical traditional Indian woman and widow. That led to basing her existence on her son.
Larger issue here is culture of dependence ingrained in female mind, having no life of her own - which makes her do anything for males.
They literally beg and crave tum mujhe chhod ke na jaana to their sons.
Sons often get more preference as it is more possible to control a young male than a husband, a full grown man. Sons are also greater insurance for future than husband. In past becoming Rajmata was a huge deal for women.
I once talked to a psychologist and she told me how older women feel almost useless and jobless once kids grow up and get married. They rant and quarrel with DIL as they innately wonder about their status and want to somehow assert their importance.
Often family oriented middle class Indian men also become more aggressive and authoritative with age as they do not want to relinquish control of family.
Problem is Indians are too emotional, too dependent and never encouraged to have unique interests, individual thinking or spend time alone. When your status or identity depends on others then no wonder you will interfere in their lives or feel empty yourself if not getting attention.