Thou hast seen many sorrows, travel-stained pilgrim of the world,
But that which hath vexed thee most, hath been the looking for evil;
And though calamities have crossed thee, and misery been heaped on thy head,
Yet ills that never happened, have chiefly made thee wretched.

Martin Farquhar Tupper (1810-1889) English poet

Proverbial Philosophy, “Of Anticipation” (1839)
    (Source)