Both Manik and Nandini are reacting according to their characters.
Manik is not big on words, he somehow cannot communicate using words. All his emotions he expresses physically, be it anger, jealousy, sadness, love, so its not a big surprise where he is coming from.
Nandini is right from her POV, I mean c'mon things are going way too fast for her and Manik is very intense in his passion and love. Its only logical she wants to take things slow, get to know him on a non-physical way. Just that the word "friends" threw Manik offbalance, he only registered the "friends" part.