I can't change yesterday, and tomorrow isn't promised, but I can get it right today. I do remember yesterday's victories to build on those, but I avoid looking down the road-it's too far. Today is easy, I can do today right. Get enough today's right and you reach your goal!
I learned at SP that beating myself up for failures wasn't helpful, and short term goals were more managable - for me that meant one day at a time!