I don't think Naina can help Preeti. Naina herself needs help from Preeti all the time and she is so lost in love that it is not possible for her to help anyone.About Karthik, last episode it was visible that he has strong feelings for Sunaina. If he does anything with Naina that will be a revenge story, to teach Sameer and I don't want that at present. Sameer may get jealous ...I too want that. But not this way. I don't want Naina or Preeti to get hurt...not Sameer too.