Moving beyond feelings of rejection involves letting go of one's dependence on others to define one's identity. Though this is simple to say, it is often difficult to do since the ego-self has had much time to respond in an emotionally reactive way to the actions or non-actions of others, without knowing that another way was possible. This ego-self has been with human beings for a very long time, and so any undermining of its habits involves determination, assisted greatly by an authentic experience that there is another way to live. If the authentic experience of the 'other way' is profound enough, the struggle to get past the ego's premises can be won in an instant.
The way of independence is the way of inner growth - the realization of the wholeness of the self. Each self is capable of experiencing this wholeness which is not dependent upon external circumstance, but on an inner perception of truth. Independence is a relative term, since we are also communal beings who share energy and soul connections with each other that are profound. But soul connections and being dependent are two very different things. Dependency is an emotional bond that has to do with karmic influences that shape identity. Soul connection is a positive bond, created out of love and joy, where two or more feel their inner kinship and identity of soul purpose.
The way of overcoming vulnerability to rejection is the way of turning to the Divine for all needs, and not just the Divine without but the Divine within.
Believe that your wholeness already exists within you and it will be a starting point to stabilize yourself in relation to the responses of the world, whether positive or negative. This stabilization is an essential part of spiritual growth, and is greatly aided by a regular connection with one's higher self.
Beloved ones, the vulnerability to hurt is within your own power to change, to limit, to dissolve in the light of greater truth. This does not mean that there will not be some residual sadness when love's purposes are turned away from by others, but that this sadness will be a Divine sadness based in compassion, not one that reflects on the personal self.