That voice in your head is the sum total of everything that everyone has said to you or that you have heard, read, or felt directly or indirectly and your own inner voice in its process of distinguishing the truth from the false.
None of us ever leave this eternal existence, so keep in mind we as eternal beings will eventually meet each other once more so make peace and reconcile everything between everyone in our heart and mind and talk directly to everyone in your heart and you will find the subtle energies of these interactions carry through to the entirety of Life, this is what the Spirit has shown me through the studies of the Holographic Field.
The inner child exists, they are not an apparition, they really are there. The voices of all other people dwell within our hearts as data-resonances, sacred resonant geometric mandalas that live in the flow of the water of our bodies and from it the soul song is heard and the soul songs of all who we have ever been with, in ultimate truth the soul songs of all beings pass through us (the water has been through everybody 7 times over), so apprehend everybody you have ever met in your Life from within and make peace with them, you will find your dreams may start revealing the true nature of things when you begin this practice and I would assure you that to succeed eternally we shall be grateful to the Absolute Eternal and to dignify and honour the journeys of all beings within our hearts