To break free of bad habits it is important to find new ways of bringing the benefits to you that the habit previously brought. Habits remain habits because, paradoxically, part of you enjoys what that habit brings so there is a sense of loss attached for changing.
For example, binge eating brings comfort, smoking relieves stress and drinking creates a happier reality. Yet all of these benefits are short term only. The effects of the cigarette soon go and a new one has to be lit, the same goes for the effects of food and alcohol. More of the fix is needed and it goes around in a circle. Somehow, the mind has linked the benefits of the habit exclusively to the habit and the individual is fooled into believing the benefits cannot be achieved by natural means.
Ironically most people indulging in bad habits know the consequences and know the benefits are short term/unreal. I'm sure today, being a Sunday, has seen thousands swear to never touch alcohol again, yet by Wednesday they will be looking forward to the same alcohol induced reality escape as they had this weekend and will pay the consequences again on Sunday. They didn't want to quit after all.
Same with bad eating and exercise; its usually not until the health problems rear their sorry head that an individual cleans up their act.
You will break free when you have established different choices that include the benefit. Exercise induces happiness, calmness, confidence AND good health. You're life will simply be better if you cut out the cigarettes and reign in the junk food.
Search your soul for the reasons you really want to look good and be healthy, be honest with yourself here. I know what it is, and its the same for everyone. Feel what it is like, how good it is. By kicking the bad habits YOU WILL FINALLY REACH YOUR GOAL. Then you have all the benefits of the old habit but without having the habit itself.