A while back, some of my friends and I were discussing this (because apparently I have a small one, too, though nowhere near the mammoth size of Ed's lumbering complexzilla), and came up with an interesting analogy.
Involving a toaster. XD
In both the anime and manga versions of FMA, Edward displays a marked tendency to blame himself for everything that goes wrong in his immediate vicinity and then obsess over it forever. To illustrate this point in conversation (without spoiling any of the more convenient exemplary plot twists for those in the room who had not seen them yet), we came up with a hypothetical situation:
Suppose Edward were to wake up one morning at the Rockbell house, bumble his way downstairs on that dorky temporary leg and attempt to make himself a piece of toast, as part of his balanced-except-for-the-severe-lack-of-d
If the toaster were to begin spewing choking black smoke halfway through the toasting cycle, give off a shower of sparks and a few rattling and buzzing noises, and kirk out...
It would, in Ed's mind, immediately be His Fault.
The first step would be overwhelming horror. HE BROKE THE TOASTER! He is a horrible, horrible houseguest! He should never have picked up that piece of bread! Oh, he is fortune's fool!!
Next would come the obsessive self-guilting. Ed would slump into a kitchen chair, angsting over all the other household members he has deprived of toast, and over the time and money they will have to spend to fix the toaster, and over his own carelessness and overconfidence in foolishly believing he could use a toaster without repercussions.
No amount of reassurance that the toaster was just old, or that maybe the last person to use it left some bread stuck in it, or that it was just a stupid toaster would comfort him, because Ed does not believe he deserves reassurance. Those around him are just trying to make him feel better about his heinous mistake. And their kindness only exacerbates his pain.
Therefore, finally, would come the recompensation phase, in which Ed would go to any lengths to repair the toaster. The two skilled mechanics in the household would offer their help in vain; for it was Edward who BROKE THE TOASTER, and only he can undo his own foolishness. He would spend days researching toaster diagrams so that he could understand and repair it with alchemy. He would go all the way to Rush Valley to get a rare part if necessary. He would walk there, in fact, because that would save money on train tickets that he could then give to help pay for the toaster repair.
Every step would be penance for his careless, toaster-breaking soul.
In the end, the toaster would be sitting happily on the kitchen counter once more, shiny and rejuvenated. But Edward would never forget what he had done to it. And he would carry that angst, that toaster angst, within him, hidden behind a brave facade...forever.
(My only excuses for this? It's after midnight, I'm exhausted and bored, and I'm supposed to be studying for a kanji quiz. And tempest_strife told me to post it. Glorious Mustanging, how we salute thee.)