Her negative thoughts accumulated need an outlet. You provide such an outlet.
Her negative thoughts help her to remove herself out of the picture, thus she bears no responsibility for herself and the situation she is in. It offers her psyche a great relief by distracting her attention away from herself and what she really needs to do (i.e., taking responsibility for herself.)
Not suggesting you say or do anything when interacting with her, just a possible explanation for what you are dealing with.
(Not everyone is willing and capable. But everyone has his own way of coping.)