I agree with all the others that Shivvay is just one of the leads in the story of the three brothers.
He is certainly no hero but neither are the other two as we will find out when their story progresses. As of now we have only seen the CV's explore Shivvay's strengths and flaws, we still have to see the other other two leads take off with their strengths and flaws.
That is what the first episode spoke about.
No human is perfect and Shivvay's flaw is just that. He thinks he is as close to perfection as one can be. He does not think he needs to change his way of thinking and his beliefs because he is always right. He says that over and over again and even said that to OM in the last episode. His opinions, decisions and ideologies are always right and unfortunately he has been proven right over and over again in his own mind.
Annika was the only person that was opening him up to that change but the ONS put an end to that and there was even further regression in his personality because of that. He trusted her and took her at her word that she was an independent, strong and self respecting girl and all she did (in his opinion and biased judgement) was made a fool of him for believing in her. That killed the new Shivvay that had taken seed and was sprouting and hence he treats her the way he does because her betrayal was in a way personal for him. (I do not in any way condone his actions before, during and after the wedding - please be clear. This is just a reply)
After this betrayal of sorts he became worse than what he was before because he made the mistake of doubting his earlier beliefs. He knew he should never have doubted them because when he did he opened himself up to only pain and disappointment. This harsh almost inhuman side is a natural response as a defense mechanism to opening up the old wound again. He has sealed all paths to the Shivvay that was forming and creating new opinions and beliefs.
For such a cruel, rigid, proud and arrogant person to change he needs to experience a life altering experience. Annika's truth, Tia's truth and Daksh's truth all coming at him in a series of events without a break or breather will be such an overload on his system that he will have no other choice but to almost die to himself to be reborn again.