Brillow I haven't had the priveledge of playing in game with you or talking to ya on the forums but if it's okay I'm going to weigh in.
I've been on almost the opposite side of Duke. Almost everyone I have met through the 20 years of my life have failed. Miserably. They all had one thing in common and in fact it was to have everything they wanted right away. They never really built themselves a solid foundation. So on their way to get to the "high" part of life, their falls were long ones.
What you are doing is very wise. You recognized your mistakes and instead of saying "it's impossible" or "I can't do it", you've built yourself a foundation. The more goals you make for yourself (weightloss, kicking the PC drug, etc..) the more you will trust yourself. The more you trust yourself the higher your determination will be. Determination isn't something you're born with, it's something you gain after hard work (which you're doing) and a positive attitude (which you have).
Another mistake people make is going cold turkey on all the fun things in their lives. They never take time out of the day to do something relaxing because they work too long and too hard. The mind needs time to rest during the day (not just when you're asleep) and an hour or two a day of fun is very beneficial. If you're worried about gaming too much, just set a schedule everyday of when you can have fun and when that time comes HAVE FUN!!
Hope this helps big cat.