A scent-less flower

Siya Singh Rajput, a modern thinking simple girl with traditional values, who at times is rebellious, suddenly transforms into Ms.Ananya Sehgal, a cold hearted woman who finds it hard to trust people. She blames only one man for this and it was none other than Mr. Vikram Rathod. What was the reason behind the transformation? Who is Vikram to Siya a.k.a Ananya?