I think before outrightly judging Gurpreet as rude/brat/'sanskaar-less".......lets see what made her react this way........ I feel she was subjected to a kind of emotional abuse by Yash's mom....
"Emotional abuse is any kind of abuse that is emotional rather than physical in nature. It can include anything from verbal abuse and constant criticism to more subtle tactics, such as intimidation, manipulation, and refusal to ever be pleased.
Emotional abuse is like brain washing in that it systematically wears away at the victim's self-confidence, sense of self-worth, trust in their own perceptions, and self-concept. Whether it is done by constant berating and belittling, by intimidation, or under the guise of "guidance," "teaching," or "advice," the results are similar. Eventually, the recipient of the abuse loses all sense of self and remnants of personal value. Emotional abuse cuts to the very core of a person, creating scars that may be far deeper and more lasting than physical ones (Engel, 1992, p. 10)."
What was Yash's mom doing..(apart from rejecting Gurpreet, which was her own personal decision...while Gurpreet had been torn between Yash and his mother's different personal decisions)-
1) She did name calling- "Ladki to bewkoof hai"
2) She had been curt..when we are living with someone...while the other person is interested and watchful and sensitive towards our behavior....a constant display of curtness is abusive.
3) She refused to even speak normally with a girl...who wanted to know what had she done to be disliked so much(lets admit-Yash WAS giving her positive signals..and she was falling for him....she had her insecurities in place)
4) She was subjecting Gurpreet to direct/indirect criticism on daily basis...gurpreet while living with her did feel the effect and pangs of constant criticism.
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I would suppose....before Gurpreet's final outburst..she must have spent a period of time in pain, depression- as I believe she had fallen victim to a temporary phase of rejection, low self worth and humiliation inflicted by Yash's mom.
I dont approve of Gurpreet's reaction...but it was an outburst of a person, who was almost on the verge of losing sanity and self respect, had she been subjected to more of curt behavior. I don't think sanskaars have too much of a role play here. Its an inherent human weakness, to cry out loud, when a person has gone through a depressive phase. Lets view her as a human more than a typical image of an 'adarsh naari'.š