The moment someone let the gap stay a gap

What you were looking at

What you reacted to in Alphonse was not fragility, and it was not being someone you could not leave alone. If it were that, the memory would put you on the side trying to help, trying to rescue. That is probably not where your memory actually stands.

Alphonse carries something missing that Alphonse cannot fix alone - a feeling, a name, a memory, a body, a sense of being worth anything. What it is changes by character; that there is no way to mend it from the inside does not. Most of the people around a character like this fall into one of two roles: they try to fix the gap, or they treat it as something sad.

What you remember is neither of those. Someone who did not try to repair it and did not pity it either, who simply did not treat the missing part as a problem to be solved. Your eyes are not on the moment Alphonse changed. They are on the moment Alphonse did not have to.

Trying to fix something, even out of kindness, is also a way of saying that part should not be there. You already know that. Which means you are not drawn to someone breakable. You are drawn to the exact shape of being left alone in the right way.

And where that leaves you now

One remembered picture gets added here. What you picked was the close, expressionless shot of Alphonse standing there, saying nothing. That is the position of being inside it.

You likely have a part of yourself you do not know how to fix either. The hard part is when people point it out kindly - and correctly, which makes it worse, not better. What wears you down is probably not being told no. It is being improved on by someone who means well.

One thing worth checking. Think of the words that made you happiest when someone said them to you. Were they words trying to change you? Or words that added nothing to you at all?