What you are "obsessed" with is the illusion of Jessica Simpson, not the reality. She is a marketable package and a tremendous amount of money is spent to present her image to the public so that her investors can earn their profits. If she is so perfect, why did her marriage fail? Why has she felt the need to get plastic surgery to correct her alleged flaws?
You talk about willpower, but who is paying you to hire a personal trainer and a chef and get in shape for a movie? Do you realize that once she signs the contract for the project, the pressure for her to be what they want her to be is enormous. She can be sued big time if she doesn't comply.
The life of a celebrity is really short-lived. Jessica is already using up her alotted fifteen minutes of fame and the next "it" girl is waiting in the wings. Do you not think that she is terrified of losing her edge? She is well aware that there is no shortage of beautiful young women who can step into her shoes, and her singing voice will not make her a legend. She is no Streisand! With a little luck she may be able to follow the footsteps of Suzanne Somers and sell her line of shoes or whatever on QVC after the spotlight is no longer upon her.
Jessica Simpson will fade into oblivion in time. Hopefully she will end up happier than a lot of celebrities that have gone before her, but in reality, the odds are against it.
Create a great life of your own. What you want is atention and recognition. Do things to get it that are constructive and positive. We only get one shot at this life and there will only be one you.