Here is a hypothetical situation if your boyfriend comes out of someone else room (imagine Anika scene in Daksh room)will you blindly trust him? Personally, hell no! You may not believe when someone says but seeing in person has a greater impact
Shivaay has no claim to Anika but he loves and respect her inspite of his prejudice on naam koon Kaandan. He has not told her but he knows that he loves & respect her, given her a special place in his life (which OMRU keeps saying). He feels betrayed becoz he trusted her inspite of his beliefs. He was cursing himself for trusting her and feels hurt. He is in a bad position as he cannot ask her if it is true as he has no claim towards her. I am not discussing the topic on money as it takes things too far...but one point is if Anika was money driven and was upfront about it Shivaay wouldn't have cared but she keeps saying independent and don't care about money, he has accepted it (which is a big deal for him)and 360 degree turnaround has hit him hard obviously his prejudice plays a big role too
Many of you may not agree but in matters of heart, expectation is high from person you love and hurt is deep.