What is substance really?  Deep in the back of your mind, do you really ever remember a time of peace and serine containment.  This can be seen as the heart of God, the joy of soul or the  compassion of the higher consciousness.   You recall that feeling of total fulfilment, like being in an embryonic sac, feeling your wholeness breathing with your experience.  That feeling of synchronizing with another, intimacy with self and the experience that is full of love.  this is the essence of the love that you miss with your heart and your soul as an addict.  Substance is a mass of inert energy crystallized into form.  It is wooden or lifeless which is something to turn to  alleviate emotion and loneliness of the soul.  Addiction can be seen as the lesser choice for a substitute of lesser quality when really what is searched for is the closeness and warmth of love.  Think of it as joining with the substance in a internal cuddle with the desire of ending the nightmare of fear and emotional pain.  You want something that will make you feel peace or fun loving joy etc, You choose a external source to create and internal state.  The two can never be reconciled, so you have set yourself up in an impossible situation.  Addiction to substance is best burned away in the same eternal flame of desire that originally ignited it.  Use the energy of longing for love to quench your endless cycle of chasing love.