From Principal Teacher of Vipassana Saygyi U Goenka's article On Addiction, October, 1991:
The intellect has its own limitations. You cannot realize the ultimate truth merely by intellect because intellect is finite, while ultimate truth is limitless, infinite. Only through direct experience can you realize that which is limitless and infinite.
If you accept this law of nature intellectually but still are unable to change the behaviour pattern of your mind, you remain far away from realizing the ultimate truth. Your acceptance is only superficial, while your behaviour pattern continues at the depth of the mind.
True freedom comes only with conquering lust - the sexual craving for another's (filth-filled *) body - which, in reality, is only craving for a particular flow of sensations (kāmā asava) within one's own body. The ascetic Gotama successfully fought through this great inner battle against lust, in his journey to total purification of the mind with practice of Vipassana. He reached the ultra pure state of a Sammasambuddha, to serve all beings with infinite compassion.
When the addictive urge arises (whether for a sexual action, alcohol, drugs, tobacco etc), along with it there is a sensation in the body. Start observing that sensation, whatever it may be. Do not look for a particular sensation. Anything you feel at that time is related to the urge. And by observing the sensation as impermanent, anicca, you will find that this urge passes away. This is not a philosophy, but experiential truth.
* Contents of the human body: hair of the head, hair of the body, nails, teeth, skin, flesh, sinews, bones, marrow, kidney, heart, liver, pleura, spleen, lungs, intestines, mesentery, stomach and contents, faeces (excreta, body waste), bile, phlegm, pus, blood, sweat, fat, tears, grease, saliva, nasal mucus, synovial fluid, and urine. This is its nature. (from the Mahā-Satipaṭṭhāna Sutta discourse)
[To see the true nature of the human body, go to Google Images, enter search word 'autopsy' ]
That aversion or craving is generated only to one's own bio-chemical flow of sensations within, not to external objects, is the fundamental, life-changing truth realized by practicing Vipassana.
May all beings be happy, be free from all impurities of the mind, be liberated from every suffering.