Is there is difference between trusting a person (rather the words he utters) and trusting the relationship one has with him? Manik seems to think there is. When he gets very close to a person he wants them to trust the relationship they have together, enough to disregard his words to the contrary. We saw that in the instance where Dhruv believes him when he said he was responsible for the goons' attack on Nandini and punched him. Manik wasn't angry with Dhruv for punching him but was disappointed with him for taking his words at face value and think that Manik would stoop to such levels. At that time Nandini bought his words too but he didn't give much weight to that then because they hadn't gotten so close although there was always the strong attraction between them.
Once Nandini and he established a relationship, he seemed to expect much more from her. When Nandini believed his harsh but untrue words spoken at the time that he broke up with her, he was hoping in his heart that she will see through his lies and stop him from damaging the relationship which was still in its very nascent stage. He was hoping that she would trust their relationship enough to disregard his words. When she was begging him to say something which would dispel her doubts about him, he even made a half hearted plea to her to stop him but Nandini was so mired in her doubts and grief to catch the pain in his voice when he was asking her that.
So trust (or rather the lack of it) was an issue for both of them. Nandini felt that he should have trusted her enough to have come to her with the Dhruv issue so that they could have dealt with it together rather than unilaterally taking the decision to dump' her for Dhruv's sake. From her side she felt she trusted him enough to believe his every word. However, Manik's definition of trust was not the same. In his eyes she had failed the trust test when she fell for his words rather than his actions (rushing to meet her at 3.00 am and hugging her tight as though his life depended on it before working up the courage to dump' her the next evening). The contradiction in his actions and the subsequent words went unnoticed till much later when she figured out the puzzle. Only what she managed to unearth was even worse, for it showed that he placed his friendship with Dhruv higher than his feelings for Nandu and was willing to sacrifice her to him without even bothering to check whether she was OK about being gifted away so easily.
So can she trust him again? Would he stand by her against all odds and show that she means the world to him, which she really does? For that he has to admit that he loves her and cannot do without her. So far all he has been harping at was her need to forgive him. Was that the only thing that was bothering him? No. He wanted much more than just forgiveness. He wanted what they had before he threw it all away due to a misplaced sense of sacrifice. That would require much more opening up from his side. So far it was all about what he wanted from her. He wanted her to be his star. He wanted her to promise that he will be in all her prayers. He wanted her to trust him. In all this he has still not said what he will give her in return. Its true that Nandini never asked him anything in return when she promised to give him everything he asked for. Her love was completely unconditional but then the fissure in their relationship which has developed, which is Manik's own making, needs to be bridged by Manik. He needs to set aside his ego and search his heart for the answers to what Nandini means to him. Nandini's decision to leave him is going to push him towards those answers I guess. It is only then can he expect and get her to trust their relationship as much or maybe even more than his words.