Along with swallowing a lot of food, her habit of overeating was swallowing her life up.
Each time she ate as a detour around feelings, or to help her out of a difficult situation, each time she lost a little freedom. Each time she ate as a response to life's ups or downs, she dulled her senses and she stole from herself.
What did she steal? - the opportunity to learn, to test out new abilities, to grow as a person.
Eating is a good thing. Eating to control problems was making Molly's body bigger and her life experience smaller.