The mind is always the first step, the decider, the influencer, and the consummate manipulator of direction and misdirection. You do not know your mind, but your mind knows everything concerning you, especially when it picks what unnerves you to create different degrees of thought patterns, which develop into feelings and mixed feelings.
The ironic thing is that, you cannot destroy your mind, but your mind in its deprived state, can destroy you. Besides, until you are discerning enough to sift the right information that your mind presents to you, it will continue to control your behavior dynamics. Your mind was created but you as a person construct your own thoughts depending on what you allow the mind to take hold of as content material.
Now, who you are and what you will become as an eventual happening, your mind was first that activity. So, to control your mind or defeat your mind, you must be able to understand what influences your actions and then make sure that your mind is not overly exposed to what can ruin your life.