DON'T have the plan on their fridge door??
Or else somewhere where it is in plain sight??
I'm not even doing the C25K plan now -- but I have a running "plan" (created by me) which is in a place where I am reminded that it is now an equal part of my life - alongside all the other important things like, family, friends, having a shower, cleaning my teeth every morning, doing the shopping, cooking meals, etc, etc.
It has to be incorporated into your everyday life -- as do diets -- not just something that you are doing "now" until you "get fit" or "lose weight". Today, tomorrow, next week, next month, next year! etc. Once it is placed equally alonside all those other things - you do not "lose your mojo" . You don't need mojo to brush your teeth in the morning ??