Sounds like maybe you're setting yourself impossible goals. Make them smaller, and don't look on it as failure if you don't meet them, just see it as delayed success.
I have printed a picture of the word "focus" (one of those photos where they focus in on the word in the dictionary and all the other words fall out of focus) and stuck it over my computer. For some reason that word works for me because I've chosen it as my word for the year. If I glance up and see it, it often makes me stop messing around and do what I'm meant to be doing. But you need to find whatever it is that works for you - trial and error.
