Man is the artificer of his own happiness.
If we cannot live so as to be happy, let us least live so as to deserve it.
The foolish man seeks happiness in the distance, the wise grows it under his feet.
Nearly all marriages, even happy ones, are mistakes: in the sense that almost certainly (in a more perfect world, or even with a little more care in this very imperfect one) both partners might be found more suitable mates. But the real soul-mate is the one you are actually married to.
As a child, I lived with being punier than other boys in class. The only consolation was my parents' empathy - they encouraged constant trips to the local drugstore for chocolate milk shakes to fatten me up. The shakes made me happy, but still, all through grammar school, other kids shoved me around.
Such is the common process of marriage. A youth and maiden meeting by chance, or brought together by artifice, exchange glances, reciprocate civilities, go home, and dream of one another. Having little to divert attention, or diversify thought, they find themselves uneasy when they are apart, and therefore conclude that they shall be happy together. They marry, and discover what nothing but voluntary blindness had before concealed; they wear out life in altercations, and charge nature with cruelty.
—Samuel Johnson in The History of Rasselas, Prince of Abissinia
Some cause happiness wherever they go; others whenever they go.