One of the key components to successfully lying to myself is that I must be invested in the lie. If during my twenties I had observed a stranger who mirrored my exact behavior of the time, I might have casually thought to myself, "Jeez, that guy should take it easy on the booze." Not being invested in his personal matters, I would have had no incentive to deny the obvious about this stranger's detrimental behavior. Yet that very same behavior, when I did it, struck me as "no big deal" because I was invested in the lie: it absolved me from the burden of answering questions like "What sort of pain or unhappiness am I attempting to soothe with booze?" My ego also stood in the way, with arms folded and chest puffed out, always insisting that I didn't need to change, always eager to fill my head with delusions of grandeur.
In my everyday life it can be exceedingly difficult if not impossible to both bypass my ego and truly detach from myself mentally, such that I can evaluate my own behavior as objectively as I would that of a stranger. But these exact abilities are two of the profoundly beneficial effects of psychedelics such as LSD, psilocybin mushrooms, Ayahuasca, etc. Later in life, specifically thanks to psychedelics I was able to look at myself from the outside perspective of someone not invested in my lie, and I saw my self-deception for what it really was. I clearly saw the pain and unhappiness that I had been trying to soothe, and I acknowledged that attempting to drown my problems in booze was not a solution but in fact another problem — one that I quickly resolved.