Mishti and Veer are from different land and era.
Mishti is today's girl. Her parents died at her young age. She had to take responsibility of her family. Now how she did that and how much she sacrificed only she knows that.
Veer and Mishti's relationship is just for one year. It is impossible to know a person in just one year. As a boy friend who would not like a guy like Veer. I mean he is super rich, handsome, stylish .....got a huge car, business etc. With that he looks and pretends like a liberal, modern man.
Then came "marriage". Here Veer turned out to be the traditional man. He is busy .......so busy that he can't take care of his family. Who will do that? Wify. Wify has her own responsibility, family, past. Skip that as wife's family doesn't matter according to our traditional belief. Well at that time girls used to get married at 4. More than mom/dad sasuma was their true mother. Na toh Mishti ki age 4 hai na woh utni nadan hai. But Veer and Veer's family was thinking like them.
Just like any other girls Mishti also tried to sacrifice her entire life( family, responsibility, career, life....etc) . To do what? Fulfill Veer's responsibility. And she was about to give up her career. I would say social suicide.
She stopped herself before suicide. So does that make her flawfull? No. Every person has the right to save her life. What is the first thing this girl did after the break up...........go back to her proffessional life, build business, buy a house so that she can take care of her family. Ruhan understands it. Veer can't. So is this her fault? Yes may be upto dating with the wrong guy Veer. Or the break up without giving a proper break up list....... about "why I am breaking up with you."