This is such a great thread. All of the reasons already stated are definitely my reasons why this time it's different for me as well.
I will have to of course put my 2 cents in
This time it was/is different for me because I finally
realized that I did indeed have control over my health/weight and that if I didn't want to be fat and miserable - well I just didn't have to be. AND I finally, finally accepted that I simply could not have it both ways - I couldn't have the high calorie/high quantity food in my life and
be that happy, healthy, fit, energetic, productive person I so badly wanted to be.