So, you screwed up. Well, welcome to earth, population: Well over 2 billion. Humanity has been waiting for you.
You have a few options here, give yourself hell, pretend it didn't happen, live and wallow in guilt, or... work on you. You cannot reach perfection in this lifetime, I'm afraid. BUT... we all have chances to show the good that humanity can do. To be kind. To offer help when needed. You might get a hand slapped away, but at least offer it. Do not be kind to puff yourself up, be kind because it is the right thing to do and people don't see enough kindness anymore. False kindness, is not kindness at all. Understand that people can and will be cruel. Understand you yourself are capable of this.
Be kind, even if people don't understand why.
Remember that you will screw up, and that it'll hurt like hell. Don't rest on laurels--- but remember what you have accomplished thus far. Don't let a set back lead you to the hell you already got out of.
Remember that you have limits, and that you do occasionally, need to rest.
The best kindness I think, that can be offered to those in pain, is to be there on the side, to offer a hand while they walk through their personal hell. "I cannot walk through hell with you, but I can be there, and hold your hand- and hopefully, keep you from falling too far."
If someone is drowning in a cesspool, do not expect explanations of how they got there, do not question. Offer a lifeline. Accepted, or not, it's there. Do not expect in return, but enjoy the small, simple beauties. Life is hard. Sad as that is, we still can be good.