Ohhhhhhhhh you sound just like me.... it's getting harder and harder to get out of bed for my workouts! But guilt is a far harder thing to deal with I've learned. Just keep DOIN' IT!! But you are smart to get the rest when needed or skip when it feels as though it will do more harm than good. As Nat says, the workout is supposed to work for you, not YOU for IT!! Listen to your body (but not your head when its trying to make flimsy excuses...that's the !!)