i agree with elvislover. making one or two small changes and sitting tight for a while just to get used to it is a great approach. no more cycles of shame. no more beating yourself up for not doing it perfect. just make one small change and make it a goal to do it for one day. and then the next. and so on.
this is a great website where you can read and learn. i wish you the best, and congratulations on deciding to make some changes in your life!