I meet few Christians who are good to themselves. We tend to view ourselves with contempt and regularly chide ourselves for our shortcomings. I do it myself. A confidante once said to me, "You'd never let anyone talk to me the way you talk to yourself." She was right.
What drives such negative self-talk? Is it fear? The fear that keeps telling us that we need to whip ourselves into shape or we'll go off the deep end?
Or, maybe it's pride. Do we in some weird way, elevate ourselves to a status that tells us there is no room for failing?
I don't mean to suggest that we should ever sugarcoat sin. Most Christians I know don't do that, but instead of straightforwardly acknowledging it and then declaring themselves to be forgiven, in keeping with God's promise (1 John 1:9), they beat themselves up. This is followed by a sense of shame, which is followed by a form of depression, which gets us stuck.
When we do this, we are aiding and abetting the devil.
Let's not give him any help. Let's say to ourselves what God says. When we sin, let's own it and then declare our forgiveness. Let's follow that with a declaration of the reality that God is at work in us "to will and to work for His good pleasure" (Philippians 2:13).
You know that God is good to you, right? Then be good to yourself!