You know Manik as a character is not as a strong as he thinks he is. He craves for relationships which doesn't call for a give and take scenario and when he gets one, it's his biggest weakness. He gets unconditional love from his friends and thus he can do anything for them, even destroy himself and that's exactly what he is all.
I know he can get all the love and affection from Nandini but then he doesn't want to let go of a relationship which is so dear to him for so many years, we don't know what all has he faced with Dhruv and what he exactly means to him. Many feel his decision is wrong, may be coz Nandini will be hurt but one thing which I feel has triggered Manik's decision is that Nandini at any cost can handle herself, we have seen in the IV interview also where she says that she will go up-to Manik and say that he will not be able to break her.
But the same is not with Dhruv, he will break down and may be he will go into such a condition where he will not be able to recoup. Thus, Manik's decision makes all sense.
So, now either it's Nandini or Dhruv who can make Manik believe that sacrifice is not always the perfect solution to deal with a situation.
