Keep at it! I know how it feels when the doctor tells you that stuff. Mine told me this week to stop drinking so much caffeine (I drink between 2-6 cups of hot tea a day) and to exercise more, and to try to lower my BP. I think there is a disconnect between doctors telling us to do this stuff (like it is just _that_ easy and us trying to do it and sometimes having to really struggle to make those changes.
So *huggles* be kind to yourself and just take it one day at a time, one meal at a time and one step at a time--those steps will add up ;)