I guess we could start with Freud's theories about our youngest selves. What I know about his theories is only from Dr. Sarno and Steve Ozanich, but supposedly the earliest loss we suffer is the breaking of the bond with our mothers, which creates the first source of rage. I am not clear whether this can be upon birth, but it's certainly upon being weaned, followed by having to share one's mother with others, such as siblings, etc. You get the idea.
Even more lifelong rage can be generated by the early loss of parental love (abandonment, via death, divorce, mental illness, neglect, abuse), or by the loss of community (isolation, via bullying or segregation). Over one's lifetime, there are any number of situations which result in the loss of connection with one or more other human beings (isolation & abandonment, plus loss of freedom and loss of meaning) and each will generate deep, usually unacknowledged, rage. As one approaches the other end of life, the rage is often about our inevitable mortality - our unfortunate awareness about the ultimate loss, of life.
Loss of connection. Loss of freedom. Loss of meaning. Loss of life. I believe that the deepest negative emotions, including rage, are connected to these four things. Acknowledging and accepting them is an important component of recovery.
