Airyn seems like a low key, nice lady. Who on earth does this to a widow with two kids?? What did Airyn possibly to do her other than be married to Art? Sick.
Her "crime" was being Mrs. Bell. Multiple people have said feathers was insanely in love with him. I bet she was under the delusion that he'd leave Airyn for her and when he died, she realized that wasn't going to happen. I'm even willing to bet that she was so sick in the head that she convinced herself it was the wife's fault, hence the shit about letters and "you all don't know what it's really like".
Still can't get over leaving the missus and kids without a ride to the funeral...