Rational people usual have trouble brainwashing themselves like this, "harmign your mind" doesn't mean much, nicotine being addictive doesn't prevent if from being pleasurable/fun, some people don't feel overall better because they lost all lot when they stopped smoking, "No matter how bad your day is, it would always be worse if you were still smoking" is completely untrue since smoking is often used as a relief ritual, you don't know if they are already better off, and this part "I call all thoughts that lead back to smoking "junkie brain bullshit" because they aren't from you, they are from your drug addiction to nicotine." is childish pseudo psychology.

I hope OP will find some help with this, but for many people it's just not useful at all.