Karma Yoga and Love

I found this great piece in "The Secret of Work" that was rather uplifting (and sobering):

"True love can never react so as to cause pain either to the lover or to the beloved. Suppose a man loves a woman; he wishes to have her all to himself and feels extremely jealous about her every movement; he wants her to sit near him, to stand near him and to eat and move at his bidding. He is a slave to her and wishes to have her as his slave. That is not love; it is a kind of morbid affection of the slave, insinuating itself as love. It cannot be love, because it is painful; if she does not do what he wants, it brings him pain. With love there is no painful reaction; love only brings a reaction of bliss; if it does not, it is not love; it is mistaking something else for love. When you have succeeded in loving your husband, your wife, your children, the whole world, the universe in such a manner that there is no reaction of pain or jealousy, no selfish feeling, then you are in a fit state to be unattached."
-- From The Secret of Work by Swami Vivekananda