I think that Mishti is justified in her reaction to Angad and what he did to her. Often people in love see that they want to see, so I can forgive Mishti's delusion about Angad's love for her. Yes, I agree that deep down she probably knew that Angad loved Kripa and she chose to ignore it. But if I am not mistaken Angad never openly admitted his love for Kripa and always gave Mishti the impression that he wanted to start a new life without Kripa. Indeed, his hatred and anger were so intense that he could have given Mishti the wrong impression.
He was marrying Mishti to spite Kripa and that was unfair to Mishti. She did not force him to accept her, rather accepted him and his shortcomings. I think she deserved an explantion atleast. I imagine it is very traumatic to be dumped at the altar...and is very normal for her to curse Angad. I might have done the same thing in her place. Afterall, hell hath no fury like a woman scorned! Whatever she did, she did because she was deeply hurt...Her reaction yesterday showed that she first denied the fact that Angad could shame and reject her (she had to first come in terms with what happened-instead of being the newly wed deliriously happy bride she expected to be, she was jilted at the alter...its every womans worst nightmare), and when it really dawned on her that Angad did not love her, she (in all her hurt and rejection) cursed Angad because she wanted him to feel her pain.
I think Mishti's portrayal is very realistic...