The use and abuse of drugs and alcohol (substances) can offer a means to escape the pressures of life, or reality, but it is always at a cost to the user.
It is important to remember that there are different levels of substance use and abuse, ranging from the casual use to addictive abuse of substances. Society, through advertising and an willingness to accept certain constructs, encourages casual use of substance. Alcohol is presented as a way to relax and unwind by putting the cares of the day behind you. More recently advertising has made it more acceptable to seek drugs to reduce anxiety, to treat depression, to lose weight, and to fix a hundred and one other problems that people face on a daily basis. A pattern is set and reinforced - it is acceptable to temporarily distort or reduce your perception of a problem, or delay dealing with it through working at finding solutions, through the selective use of substances.
Addictive substance use and abuse carries this to an extreme, but is rooted in the social acceptance and promotion of the concept stated above. For though there may be a bio-chemical tendency toward addiction, there is nothing that says addiction is inevitable. The initial casual introduction of substance use as coping mechanism through the socialization and learning process can lead to stress induced maladaptive problem solving - viewing the substance induced state as solution rather than a temporary delay of dealing with reality.
This can lead into a vicious cycle where the inability to face the discomfort necessary for problem solving and growth leads them into increased substance use and abuse. The addiction that follows can either be psychologically based that become bi-chemical through repeated use, or bio-chemically based that becomes psychological through repeated use to avoid problem solving.
Either way, escaping from reality, though temporary, becomes an attempt to escape from the view of self. And at the point of addiction the view of self as addicted is unacceptable, and therefore denied. But the awareness of the necessity for a cognitive self reemerges once the effect of the substance wears off. This feeds the cycle by inducing guilt at the failure to gain control. And the need to escape emerges once again.
This is why addiction treatment involves far more than just removing the substance from the person. It needs to include supportively reintroducing the person to reality, and providing support as they build or recover the problem solving and coping skills necessary to function as adults.