Do we need to cheat the mind to escape thoughts which would lead to bad habits?

Do we need to cheat the mind? For example: - A thought came: "Why not get Drunk tonight?" (I don't drink & smoke) - Next Thought: "No I am not supposed to do it" (is this 'mind' talking again?) - Next Thought: "Oh Come on, Don't be a child." - Next Thought: "No my room mates are good people, I can not." When I think about it, I came to know that my friends are also a major fact in helping me in making good habits. But what if someday I am with some guys, who are always drinking, and there is no pressure of insult? How to control mind? Is observing the feeling of lust actually helping me to know more about it? Is it true that we can never control the mind, and that we just have to cheat it by either focusing on some other thing (which is just to avoid the feeling, but it will come back), or to observe it? What exactly happens when I observe a feeling or sensation in the body? What is the best way to change a bad habit? Someone told me to know the reason why I want to change it, but would that be enough?