I am large, I contain multitudes
One way of describing what is happening within the psyche of human beings is the theory that we were once whole and at some point in our lives we have split our personalities in several fragmented parts. This seems to be a normal stage in all of our lives, for some related to difficult childhoods though other psychologists say it could even happen when we become aware that we are separate from our environment. This sudden realisation brings about fear and anxiety attached to the sense that we are completely dependent on our parents for our survival. This means that we realise quickly we have to make an effort to keep this dependancy going. In order not to rupture the bond between us and the outside world, we observe and learn which aspects of us are unwanted by our parents or the social group and we split our personalities and disown parts of ourselves that are dangerous for our survival. This all happens at a very early age and most of us don't remember doing this consciously. Some however do have a memory of the state before becoming aware of separation.
We learn some thoughts, feelings or desires are unwanted and combined with the vague memory of wholeness, happiness, we start searching it outside ourselves.
Walt whitman had it right when he said:
" Do I contradict myself? Very well then, I contradict myself, I am large, I contain multitudes."