The excessive clinging is the most frequent manifestation of structured emotional dependence on another person, which is often taken for love. Such intense and intractable attachments, however, invariably lack the very ingredients required for genuine love-delight in the other person in his or her own right and in the person's own way as an independent being. The clinging love is a counterfeit love and tends to deprive one's partner of a life of his/her own. Such people's love does not even discriminate among partners; having love needs met becomes more important than who meets them. This motivation harkens back again to the infant-mother relationship, in which one is not interested in who provides the milk and sings the lullaby as long as someone does. For such a person a loved one is needed not as someone to relate to; he/she is needed to fill one's inner emptiness.
Healthy attachment requires healthy distance. A healthy distance is accomplished by allowing, if not making sure, that one's partner's separateness is secured. The poet Rainer Maria Rilke's advice for a happy relationship is for each person to protect the solitude of the other, never mind his own. Only by being separate can one be together.
Adapted from The Art of Serenity