You can't feel.
You haven't been able to feel for nearly 4 years now, so long that you think you're forgetting what it was like to have a sense of touch, like a blind man begins to wonder what a tree looks like, or a deaf woman that can only imagine the sound of the orchestra playing. You see a tree, can hear the branches creaking in the wind, but you cannot remember the feel of its bark under your fingers. You cannot remember the sting of Mr. Rockbell's violin strings when your brother flicked them at you.
But you never thought of it as a handicap, did you, as something just the same as being blind or deaf. You can't feel; once you could, and now you can't. The taboo you commited is like scarlet fever or smallpox—it snatches away a sense you never realized was so vital—and left you longing. And as far as you know, you'll be that way until the day you and your brother die, looking for the cure.
You cannot think of it as a handicap, perhaps, but handicap it is, and like the blind man relearning to walk you must relearn to touch, to not break, to not crush with those huge unfeeling hands. You keep practicing, every day, because your older brother is trying too, isn't he? He's about have the automail installed, and you are still bending metal tools in your fingers. When your brother said one year, you knew it was your deadline, too; you had to seem natural in the unnatural body.
Eventually, you make it your only policy to treat everything with the utmost care, barely grasping the china cup that you cannot feel between your fingers, like a crystal bird. You cannot even feel pressure; you lean to feel by sight, to see the signs of too tight or too light a grip before anyone else, to save face. To look normal.
You think that you will not let this hindrance keep you from leaving for Central with your older brother. He too needs careful handling, which you have mastered.
You wave goodbye to Winly, and it's odd when you cannot feel the sadness of departure.