The obvious difference between your patients' condition and the "bread of shame" is that an anorexic feels shame over what she (or he) thinks she's already done wrong, whereas arriving in the next world and discovering that you're "eating" on God's account without having independently earned it engenders regret over what you could have done better but didn't.
An interesting similarity between the two, however, is that "nehama d'ksufa" sees food (bread) being used as a metaphor for the very object of a spiritual person's striving - closeness to God in the next world. In classical Torah sources (especially the book of Proverbs), the metaphor (mashal) is always more than just an abstract example employed to teach an important lesson (the nimshal), but is also a statement about the inner construction of the metaphor itself.
Bread (and food in general), perhaps, could thus be presented as much more than mere gasoline for the human engine or objects of base desire or revulsion. Rather, bread is a gentle and delicate kiss from God Himself; a soft whisper saying that He cares enough for us a human beings that He's willing to trouble Himself to create an entire world to sustain us. Eating properly (which includes expression of our appreciation through making blessings as well as concern for health) is one way to approach the sublime Divine presence while still in this world: He cares...I'm already basking in His warmth.
Perhaps the following idea could add some punch to this point:
Rabbi Moshe Chaim Luzzato (18th Century Italian scholar), in his classic work â€˜Mesilas Yesharim' demonstrated the impossibility of satisfying the soul in this finite, mundane world (when teaching this idea, I use the example of fine art and classical music: in great works of art, you can sometimes almost taste an unsatisfied and terrible yearning for something more, something just beyond the artist's grasp. I suspect that might be one reason why so many artists are so depressed because they can almost see it but don't realize it's not really in this world at all...).
Either way, given that the soul can never be truly happy here (and assuming that God created it for some benevolent purpose), there MUST be some time and place where it WILL be satisfied. That place, writes Rabbi Luzzato, is the next world, where, in proportion to our worldly merits, we will bask in the infinite warmth of the Divine Presence...something we strive for even now without necessarily knowing it.