(Beautiful words from the Ba'al Shem Tov)
"Don't get carried away with excessive details in everything you do. This is your evil impulse working against you.
It intends to agonize you by insisting you haven’t fulfilled your obligation, just to make you depressed.
Depression is a reprehensible attitude, the greatest obstacle to serving the Creator, blessed be He.
Even if you stumble in sin, don’t wallow in misery. That would destroy all that you have accomplished so far, rendering you an easy catch for the evil impulse, since you feel you are a lost cause anyway. Your divine service would fall apart.
Just be saddened over the sin, ashamed before the Creator, and plead to Him to absolve the bad you’ve done. And then get back to rejoicing in the Creator, blessed be He, since you thoroughly regret what you did and have resolved in your mind never to do foolish things like this again.
Even if you know with certainty that you haven’t fulfilled your obligation in some area because there were so many obstacles, don’t let that get you down. Consider that the Creator, blessed be He, examines all hearts. He knows that you wanted to do things as best as possible, just that you were not able. And then strengthen yourself in joy in the Creator, may He be blessed."
—Tzava’at Harivash 46