Feelings of jealousy and envy often bring up a sense of shame or insecurity. Yet both jealousy and envy arise even in early childhood as we vie for parents’ attention, desire a sibling’s toy, or jockey for a positions in friend groups. And, as feelings of romantic love come into our lives, it’s the big emotion of jealousy than can have a way of creeping deeper into our relationships. If left unchecked, jealousy can foster anxiety, tension, resentment, and worse. But I’ve found that if...