[...] I can no longer adapt my mood to Siegfried; my musical sentiments have already far outrun it to a place which suits my mood—the realm of sadness. Truly it all seems to me—as stale and superficial as can be.
You can have no conception of our loneliness now, and as to my health, I feel heavy as lead. [...]
Source: Letters of Richard Wagner, Vol. 1, selected and ed. Wilhelm Altmann, trans. M. M. Bozman (J. M. Dent & Sons, 1927), No. 323