If you find yourself in the middle of a battle and realize it's not going so well - don't be so hard on yourself.
If circumstances have settled and things did not turn out the way you wanted them to - don't be so hard on yourself.
Life is life and we simply don't have that much control over what happens to, in and around us in it. As mentioned previously, the best we can do is try to 'control' ourselves, but even that has its ups and downs. Some days self-discipline comes with ease and some days it's like reaching for the stars (pretty much impossible).
But don't be so hard on yourself.
Remember: You did the best you could. You used all your best resources. You maintained as best you could your integrity. You gave it all that you had to give. And if you didn't - remind yourself you'll try better next time.
Sometimes a battle is more of a growth opportunity than anything else. For you or for that person in your life that sees you as a role model. Learn what you need to, teach what you need to and move forward.
Don't be so hard on yourself. Just move forward.