You're talking about a different generation of women.
Very frankly, in that generation there are many cases of domestic violence, abuse etc and still the women will stay.
We don't know anything about Anjana. Is she educated ? Would her family family support her if she left her husband? Would they atleast initially help her out with expenses, etc. if not then where will she go? Mr Hooda is a big shot judge/ maybe a lawyer at that time. So even if she goes through a divorce no idea how much time it will take, plus her kids custody and not to mention the stigma of a divorce. Also, in this society, many people even judge the kids of a broken home and don't look at them as potential spouses for their kids. Forgive me, but it isn't as easy as YAY! She shoul have walked out.
Also, MANY MANY couples stay together even after an ema. Some people decide to forgive their spouse if the spouse is genuinely sorry or if it really is a case of genuine regret. In any case, it is The couples decision and Anjanas decision. Who is Adi to interfere in his parents relationship with each other ? Oh, it absolutely sucks to realise your parents aren't infallible and are actual human beings who make mistakes like the rest of us. Frankly, I think the moment Adi started behaving like that his parents should have sat him down and told him to behave himself and that he doesn't know the intricacies of their marriage.