[a student of John Piper's mentioned someone whose experience of loving when there was no joy led her to say, "Love in action is a harsh and dreadful thing" which the student felt undermined Piper's thesis of christian hedonism. Piper responds...]

Don't jump to the conclusion that there is no joy in things that are "harsh and dreadful." There are mountain climbers who have spent sleepless nights on the faces of cliffs, have lost fingers and toes in sub-zero temperatures, and have gone through horrible misery to reach a peak. They say, "It was harsh and dreadful." But if you ask them why they do it, the answer will come back in various forms: "There is an exhilaration in the soul that feels so good it is worth all the pain."

If this is how it is with mountain climbing, cannot the same be true of love? Is it not rather an indictment of our own worldliness that we are more inclined to sense exhilaration at mountain climbing than at conquering the precipices of un-love in our own lives and in society? Yes, love is often a "harsh and dreadful" thing, but I do not see how a person who cherishes what is good and admires Jesus can help but sense a joyful exhilaration when (by grace) he is able to love another person.

John Piper. DESIRING GOD: MEDITATIONS OF A CHRISTIAN HEDONIST.