That is one possiblity - based on the research it is very clear that ME is not psychological, hence there's no rational way for LP or other psychological therapies to cure it. There is also plenty of research showing that these approaches don't work with ME.
The other possiblity is that she has ME but is in denial. Many psych therapies for ME, especially LP, focus on denying symptoms and/or attributing them to something other than ME, such as catching a cold or being older. This can be compounded by investing a lot of money in a treatment. Even once someone has realized they are still sick, they might be too embarassed to admit they were wrong when they said they were cured.
It's really just a cleverly marketed form of brain-washing.
In denial? Before LP She couldn't walk down a corridor without collapsing and now she's just booked a hiking holiday in Greece next summer. I work with her every day and her instant transformation from seriously ill to running 5km is still there - she hasn't regressed, she's not in denial she has been cured of whatever it was she had - 6 months down the line she's remarkably well and planning a Marathon in 2015. To say its brain washing is an out and out lie or ignorance of the process - and further evidence that this site is full of folk who are putting off people who might benefit from LP