To get an idea of how simple/single minded she is, here is a panel where she is worried about how fat her toes are.
She should really go to the doctor about her eating disorder.
She is so out of touch with her body that she believes her fat cells are more conscious than she is.
She hates herself so much that she seeks to absolve herself of all responsiblity for her body.
Finally, however, she decides to try to come to terms with it.
However, Cathy shall never be free of body-neurosis...
As long as her body image controls her emotional life.
But maybe, just maybe she can sublimate.