Self control is a function of
will, which does not require either
burning desire nor trauma to achieve.
The basis of self control is simply
mastering one's trivial desires so that one may fufill a greater goal or desire, be it intellectually or emotionally motivated.
I can decide I need to eat more vegetables to stay healthy, for example, without any great passion about health, or even a great lack of health, if I simply logically analyze the benefits I will gain from doing so, as opposed to not doing so, and decide that to do so would be the better course of action. In this case, discipline would be required to maintain this course of action, until it became habit, because one does not derive an immediately noticeable benefit from such a
choice, so one has to keep trucking even without having cessation of want to signal that one is doing what one should do.
In fact, THIS is
true self control; the time when one does something one knows must be done, but that one is NOT strongly motivated to do. If I have a driving passion to create a work of art, it is surrender to this passion, not mastery of myself, which has made me stay up days in a row to complete it. If I start driving carefully because I almost died in an accident, I am merely reacting to my fear of death.
Discipline is knowing what must be done and doing it, even if one mourns that one must forgo things which one wishes to do or have.
Contrast this to grinding one into one's duties, often as a means to escape
personal problems; one is the art of seeing and doing with wisdom and purpose, the other is simply an indirect means of self gratification.