She wasn't jealous when Arnav said he would leave home if they didn't accept Khushi. She wasn't jealous when Khushi was the only one who could understand what he was saying. I think these things are much important than waiting for him at dinner.
Why on earth would she be jealous if khushi was waiting. She fasts for Shaym all the time! She just knows that Khushi is a foodie and ArHi have been having problems recently. Plus she knows that Arnav has trouble accepting it when someone shows love/care towards him. He was even telling Anjali that there is no need to feed him herself. So she was a bit suspicious and concerned about what was going on and what it might lead to.
Yes Poojali is delusional and clingy but she is a beautiful human being. She is not going to become jealous and ruin her brother's life.
P.S: To those who are disappointed by Anjali feeding Arnav instead, It would have been out of character if Anjali didn't come to feed him. She always comes to him with food and often feeds him too when he hasn't eaten. I am glad they didn't make Khushi feed him to give us a rabba ve moment. Anjali-Arnav relationship should be kept in mind as well. Don't bash the beauty of their relationship because you wanted to see khushi feed him.
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