Prerna's what , why and how looks slightly clearer.
She'd to sacrifice her love and get married and after that she was miserable for a while. But she picked up herself soon because life doesn't stop for anyone and we must live through the rough edges of life and live out the tough choices. She was calming down even before knowing Kuki's truth . When she found out why Mr. Bajaj's real reason behind marrying her, it gave her a purpose in life as well as some footing in their marriage. For some one like Prerna, marriage, loyalty and commitment are very important. So she decided to stick to her end of the bargain with her head held high and with grace and dignity. It also eased her life and helped her that she quickly fell in love with Kuki so that her responsibility didn't feel like a big burden for her .Also Kuki's love helped soothe her soul. She slowly started knowing her enigma of a husband more and realized there's more to him than meets the eyes . He's softness beneath his hard shell . It all eased her cohabitation with him. They fell into a semi awkward semi comfortable grudgingly mutual respect dynamics. As of now , she has no plans or intentions to leave her marriage and since she's not thinking about such a thing , any such push annoys her. She's becoming mature and responsible. She's learning how to put her foot down . She has no intention to start a fully married life with consummation and all but since her husband's doesn't want any such thing too , she is free in that quarters.
Now she needs to think about the past chapter of her and how to close it best. She hoped making Anurag hate her will work but right now it's not working so well . So she could some thing else . She could tell him the truth but also tell him in clear terms and decisively NOT to come after her after this and if he values her sacrifice he should respect her wish and move on.
If it doesn't work ask Mr Bajaj to return the house papers and ask Anurag that he must return the BM to Bajaj. And then return to their house.
Also meet with her family and ask the Sharmas to accept her marriage after telling them the truth and bridging the gap.
If Anurag harasses her after this , she could easily stop caring and take strict actions like restrain order put on him. If he agrees to respect her decision and maintain distance yet love her from afar all his life, then she needs to respect that too since that'd be his decisions and she can't force him to move on unless he forces her first.
If Anurag finds peace and move on for real , well and good . Isn't that what she wanted or at least claimed she wanted??