Cecil made that point assuming you have a certain level of discipline. By your own admittance, you don't have that discipline.
Improve your discipline, as well. This will probably be the crucial point for you, that is, you'll learn more discipline through getting out of debt, which should hopefully keep you out of debt.
Load yourself up with blogs (if you use an RSS feed aggregator) about debt, personal finance, etc.
I Will Teach You To Be Rich Get Rich Slowly
I have a bunch more, if you're interested. They not only give great into, but can also serve an additional reinforcement and motivation.