I think it implied to the one that he love is the old Ed before things get complicated after the surgery and his denial, it made ed confused and change into Ed in the present that already doesn't care about him because of the miscommunication that Chang start first
Yes, you’re right. And I think different from Chang, the teenage Ed saw Chang as his older brother, since he played the role of his death younger brother, the teenage Ed searched for love from his brother (not in a romantic way) and his grandmother now becomes the growth Ed just hated Chang after he gave Ed a hardships life. That makes Chang feels like “the one I lust for is dead” when he confesses with the shadow of teenage Ed. Poor him, poor them.
Chang saying "the one I lust for is dead" got me like ... (ಠ_ಠ)>⌐■-■ What does it mean???? He likes Ed because he liked his brother???? Also I feel bad for him, he's kinda stupid