i think that shika was in luv with someone else and that was the person who was writing the luv letters to her.....but something must hav happened to him(i think he must hav died) thats the reason she lost her mental balance and was unconsionce and maybe abhi was the first young male she saw and thought that he was the guy she was in luv with
and abhi is sticking with her cuz she will kill herself if he doesn't maybe that is his majboori.....and thats why he does not want to hurt her feelings....and thats why he is sacreficing his luv
what do you think plz reply