[RCF]

Heygi has alluded that he is not thinking where Nikita will end, only she will be happy and will keep people around her happy. She has not been very rational in her choices, but has kept her commitment to Tharun.
Tharun is not comfortable with the depth of her relationship with Jay, that is probably the reason for writers stress on "transparency". This transparency bit is unantural or may show the control Tharun has over her. May be she is worried about being misunderstood. 
The leeway she has given Tharun was never given to Jay.
Change should be for better, not for sake of change.

Tharun should have offered her to leave him and live with Jay once he found out the truth about Jay's love, he didn't so whether he is good or bad is immaterial, Question is what will Nikita do if Mithra fight for Tharun and not give up easily, if hers is also true love....Her transparency was apparent from the beginning but what about Tharun, obviously you have seen his mother's reaction...can she take same from Mithra...

Not always Tharun can decide everything, Nikita is at a stage where she struggled a lot to be here with Tharun, Did Tharun put in same efforts is what needed to be seen , if Tharun and Nikita meant to be together at the end then so be it at the cost of so many people's hearts and hurt them and live over them....its Author's choice not necessarily need to be the right one for those who read the story....I am even if she walks away without a man in her life at the end though tough choice but ending up with Tharun seems pointless for writing 20 chapters just to show journey of Nikita if it was only meant for realizations sake and not act on it...

~RCF