In Coelho's The Alchemist, the lake cries when Narcissus slips while admiring his beauty on the surface of the lake, and he drowns. The lake's tears are not so much for the sake of Narcissus (who was wholly infatuated with his own looks) as they are for the lake's sake. For oddly enough (and ironically), the lake is just as narcissistic as Narcissus was. While he wanted to look upon his own beauty, it was in his eyes that the lake was able to see her beauty:

…when Narcissus died, the goddesses of the forest appeared and found the lake, which had been fresh water, transformed into a lake of salty tears.

“Why do you weep?” the goddesses asked.

“I weep for Narcissus,” the lake replied. […] “I weep for Narcissus, but I never noticed that Narcissus was beautiful. 
“I weep because, each time he knelt beside my banks, I could see, in the depths of his eyes, my own beauty reflected.”

The goddesses are certain that the lake weeps for the loss of Narcissus because he was so handsome. The lake (personified in the story) never noticed that Narcissus was handsome, anymore than he noticed that the lake was beautiful. The lake surprises the goddesses by admitting she was enamored of her own beauty reflected in his eyes, and we can infer her tears are falling because she will never again see her own beauty. The lake is actually crying for herself, for her own loss to see herself, and not for the lost Narcissus.