First of all.. I dont think the dress BM showed to Suhana was western dress. It was a fancy without sleeves blouse..to be worn with a saree. Secondly, when people talk about not changing themselves after marriage... I really dont understand. Change is part of life..Growing up and growing old.. all include change. And so does marriage. From her discussion it seems, her husband bought these kinda gifts.. a subtle way of saying he wants her to dress little sexy/modern whatever. He never forced her for this..my husband always liked to get up late. but now he makes morning tea for us early morning, not because he likes to do that but because I like that and he loves me.Similarly I also do things for him which I would not have done myself, just because I know that makes him happy. This does not mean we have changed for each other and we should not change just because we are expected to.
The catalyst of BM & Iswar break up was them floating apart. Stopped caring about one another and more busy with their own world. Husband in his work and BM with the family. What she was trying to say is.. it had become a dead relationship as none of them were giving time, importance and closeness to each other. A very common mistake that happens with married couple, specially after few years of marriage.
What she is saying is that they both made a mistake and thats why she does not hold only her husband responsible for this. and thats why no anger for him...