And about Mohan, Mohan is in character for saying that in front of all. But that doesn't mean it was a tactful thing to do. Being in character and making sense through the character, and outsiders judgment are two different things.
Did the others at that gathering really not have thoughts going through their head? Just because they went on playing with him and having fun, they wouldn't have talked about it as soon as he left, or when they went back to their own rooms?
They most definitely would. They also noticed Kastur's leaving, and they most likely knew why she left too.
Mohan was right in character to say the truth. But to the world, they will not think well of him.
As for Mohan's not loving Kastur. He knows what she believed, he knows her feelings. Yet he planned on going about it casually, taking on the basic responsibilities. No matter what, that is highly unfair to her.
Good that the truth has come out. And now they are on almost equal footing, and have an understanding. But that wasn't the case before, and neither would it have been the case for a long time had it not been for that truth or dare.