It is an endless cycle of anger turned inward. 90% of the people on that show have suffered some sort of trauma and this is how they cope.
You can eat to the point of euphoria, which I am sure everyone on this board has done at some point, and if you consume enough sugar you'll nod off just like a heroin addict. Studies have shown the dopamine release of a sugar high is very similar to narcotics. The problem with food is that it is necessary for life and doesn't have the stigma of chemical addictions. People are quick to say "Have more willpower!" or "Just skip a meal!" and anyone in the throes of addiction will tell you it has the complete opposite effect.
Family members don't want them to die, but they want them to be happy. You'll give up all your high ground morality once you've had a loved one crying on the phone that they can't get better and all they want is to be happy. Tough love DOES NOT WORK WITH THESE PEOPLE. NEVER HAS AND NEVER WILL.
Unless you've been there you'll never know. It's pointless to speculate.
