No considerate man can approach marriage without deep concern. I, he will think, who have made hitherto so poor a business of my own life, am now about to embrace the responsibility of another’s. Henceforth, there shall be two to suffer from my faults; and that other is the one whom I most desire to shield from suffering.

Robert Louis Stevenson (1850–1894) Scottish essayist, novelist, poet

Essay (1880-01/02?), “Reflections and Remarks on Human Life,” § 10.1 “Marriage”
    (Source)

A collection of aphorisms and musings, first published in the Edinburgh Edition of his Works, vol. 28 (1898).