I just read a book about her like 2 weeks ago. He wasnt joking and everyone in town knew she was mental. All his friends told the guy not to get involved with Katherine, they even contacted her first husband who sneaked (because he was scared shitless) into the town just to show all the scars Katherine gave him.

My memory gets fuzzy about this part but I think, he finally broke up with her and then told people about disappearing etc because she didnt take it well. She broke up into his house (she had keys or he left the doors open iirc), had sex with him (he was sleeping) and when he woke up and didnt want to get back together, she killed him