However true, that you always need to refer back for the reason of your gambling. Regardless of how tough you are you will still be tempted and tested. That's why your biggest enemy in gambling is not the casino but yourself. Greed and fear will attack you and will push you to do something irrational that is outside your plan and will derail you to your reason. That's why I think along with a strong reason, you also need a good circle of people to support and remind you "Why you are doin what you are doing."
Seems like a lot of commitment when you are playing gambling when you said that your only enemy is yourself. You will only think about this kind of deep thoughts on gambling if you are already doubting yourself. Probably you are playing with strong attachment to your money which you can’t afford to lose that’s why this kind of emotional problem plays a big factor on your gambling.
You should play just for fun no string attached to your money in able to have free mind. You don’t need a circle of group to remind you what’s your reason for gambling because it should be always for a source of entertainment. Nothings big deal on gambling if you will just play using an amount that you can afford to lose.