Emaan is quite impulsive! I guess writers chose this trait to show that she is flawed!
Salaar's Mamu very clearly blamed her father of being greedy and wanting his daughter to marry Salaar for money and Emaan went ahead and proved mamu right ! And once again she didn't feel the need to inform or discuss with her father.
How does this help her father in any way. I hope she thought this through. Otherwise, this would be yet another impulsive decision which luckily will turn in her favour.

. Bichari Imaan
. But did he thought that Saalar is rah chaltey ladkey?
. Disappointed by Imaan father. Saalar did so much for him still
. Tabb bahut maza aayega. 
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