I saw your post and decided to reply without reading everyone else's replies first. I hope I am not repeating what someone else has already said, but here goes:
I replied quickly because I TOTALLY relate to what you are saying - and I am supposed to know better! (I actually have several degrees in nutrition/natural health, etc)
Nutrition and exercise are essential, yes. No argument. But - are you (and I) asking ourselves the right questions? The real issue at hand is, why are we committing various acts of self-sabotage? Why are we hurting ourselves? What is the real issue here?
The truth is: We don't love ourselves enough. We don't feel worthy enough. We don't trust ourselves enough.
I have been having a lot of chats with my "inner critic" lately. Many people say, "ignore that inner critic," but that's not good enough! You have to reverse engineer that voice to be your inner supporter, encourager, and lover. Yes! You must love yourself, or you will forever be sabotaging yourself!
My own family recently took me to the doctor's to see if I was manic/depressive because I have so many self-sabotaging behaviors. Of course the doc put me on anti-psychotics even though his own examination did not reveal any mental illness on my part. He took the word of my family over his own examination and prescribed. I took them and had a major psychotic episode within 24 hours (a pretty good indication that I am not psychotic!! The drugs cause psychosis in healthy individuals!) Since I cannot take the meds, I must work on this within my own head (or seek a therapist if you feel you cannot do it on your own.)
I started by writing down every self-sabotaging behavior I have INCLUDING my obesity. Then START LISTENING TO WHAT YOU ARE SAYING TO YOURSELF internally. I think you'll find your problem.
Say, "I can," every time you hear yourself say, "I can't." Strengthen your resolve, encourage yourself. Be your own best supporter.
YOU CAN DO THIS!!!
WE will do this! Together! EMAIL ME and we will make a pact with each other to be our own best lover.