Christian Science has worked for some

[Baby Face Nelson]

I like Mr guillotine n knowcheeze especially

[Mumm Ra]

hypnotherapy also pretty much follows the same principals as I think you're referring to, except its someone else assisting you with the affirmations rather than yourself.
I was sure I saw an athlete mention it on TV at some point, and sure enough if you google it most of the greatest athletes use it, and many actors used it to help weight loss (break eating habits). im sure they have it more down to a science than 'christian science' too

[Baby Face Nelson]

I'll look into it thanks for that

[Baby Face Nelson]

Really need to ditch this tobacco habit. I'm trying to eat right but I smoke

[Mumm Ra]

Metu Neter books go into that

basically its easier to quit if you make yourself develop guilt, or a real negative emotion toward something via visualization and affirmation (to make a long story very simplified)
that helped me to quit drinking soda altogether for 12 years, and pork for the most part but I cheat sometimes because omelets are fucking delicious. Never was a smoker though.

[Baby Face Nelson]

I smoke rollups n sometimes cigarettes but mainly rolling tobacco