I saw this picture on a various of Facebook friend profiles. I really love what is says and try to take it to heart. I had an idea of this when I started running (and trying to get back into shape) and it kept me moving towards my goal. This picture sums it up into one thought.
Bottom line...don't give up and don't sell yourself short!
We're all human. Not suceeding one day doesn't mean not trying on the next day. Make a goal, make a plan, adjust the plan as necessary. Good luck!