It is also good to love: because love is difficult. For one human being to love another human being: that is perhaps the most difficult task that has been entrusted to us, the ultimate task, the final test and proof, the work for which all other work is merely preparation. That is why young people, who are beginners in everything, are not yet capable of love: it is something they must learn. With their whole being, with all their forces, gathered around their solitary, anxious, upward-beating heart, they must learn to love. But learning-time is always a long, secluded time, and therefore loving, for a long time ahead and far on into life, is: solitude, a heightened and deepened kind of aloneness for the person who loves.
Rainer Maria Rilke – Letters to a Young Poet, #7