Yes, I would bet that whatever happened on the flight was so disturbing to him that he will never be able to look at her the same again.
The other thing was the revelation that the number of times she hears "you're a great girl, but..." Have that discussion in private therapy session. Instead, she's put it in his head that no one stays around -- that there is something wrong with her. A confident person is like hey, didn't work out and that's a good thing.
So to me, he sees unbalanced (the flight), insecure (everyone leaves me), dramatic (everyone leaves me), the unsexy (agai