Shehnaz will not give up, but Sid is too clever for her to use the way she intended to use.
I think that she did manage to fool Sid for a while that she actually liked him and was not playing a game...but her badmouthing her own parents was the tringg tringg for Sid's dimaag ki ghanti...He was like ye bandi toh game ke liye kuchh bhi kar sakti hai...I think that is when he realized how fake and cunning she is.