I myself had a hard time to decide if he is pretending or not pretending... and still have so don't take this as my final opinion !! :)}
But somehow I feel that there is a larger reason why he wants everyone to hate him and s repeatedly asking Ishani to go out of his house or break the marriage..
He was the one who always believed in second chances pre-leap .. And after Ishani's confession that Chirag tried to rape her, he did not believe her, that sounds very fishy., how much ever he is upset, he knows Ishani wont lie about that..or at least he could have made effort to find out what was the truth.. but we don't see any of that..
As per the track, he is upset that she trusted Chirag and believed that he killed Mota bapuji, but that is what actually he was planning to make her believe.. now his situation is odd because Ishani knows that he was innocent and he does not have any other way to unite her with her father.. and worst she has started loving him dearly which he can very clearly see..
If he was just upset about Ishani having gone to Chirag and betrayed him, he has every right to be upset but the way his character was earlier, he could have recovered from it in a much better fashion, currently it looks like he is trying to take advantage of the situation to behave in a bad way (which he would not have done normally) and make everyone hate him..
I have doubt on Chirag being involved because in the KC episodes, it was shown that the watchman called Chirag before Puneet and RV arrived at the office in the night.. and for some reason Chirag wanted Ishani to also come to the same place. he had no idea that RV would be coming there. that was really weird unless Chirag had some other plan..
Of course, all speculation !!! Take it with pinch of salt !!