I personally just keep going back to the fact that essentially I quit smoking every day from the time I turned 21 until I was finally successful at age 30. I finally did something different enough that it stuck. Dieting is the same way, but harder because you eventually will have to put something in your mouth to survive. Add to that the years of misinformation and it is no wonder it has taken so long.
SING IT Girl!!!!!! Even if it doesn't work out, every experience makes you a better performer.