The melancholic identifies himself with what he has lost, that's what Freud says, according to W. The shadow of the object falls over him – the shadow of what caused his self-revilings and self-reproach.
My shadow – isn't that the origin of the lowering of W.'s self-regard and his delusional expectation of punishment? The shadow of my life upon his life – isn't that why he feels so unworthy, so wrong?