Just eat healthy foods instead. You won't crave the fast food when you aren't hungry. Soda is the same way. Keep a large glass of cold water to sip on all day every day and you will be sick of soda soon enough. I don't even care for it in mixed drinks anymore.
It's bad for health and you will gain weight so you better stop taking it and if it is too hard just eat less and less of that every week and at the end stop completly. You can treat yourself with a pizza or something for some special ocasion.
From one addict to another, stop eating it cold turkey, after a week your body wont crave it as badly and when you do try to eat it wont taste good