There comes a point in every Christian's life--and it circles around sometimes--when s/he becomes revolting to himself. This of course presents an opportunity, because we might not understand the depths of God's love for us in the moments of our failure, but we have a chance to recollect, and begin again.
Unfortunately, there is also an opportunity for someone to say, "Look at this, and look at me! I might never have believed in the first place!" This is of course foolish, but we do it all the time. Many of the people who go on and on about how horrible they are are actually proud of themselves; that is to say, too proud to turn around.
But grace is grace. We didn't earn it on the first day, and we can't earn it today, and we won't earn it on our last day. We never have actually deserved anything of ourselves. As a professional screw-up, I can offer first-hand testimony about this.
I guess I'm going to have to keep saying it, first of all to myself. There is no Good News, if it just means we put a pretty shine on things, and pretend that we would never do all sorts of things. When we examine our conscience, assuming that it is still sharp, whatever comes out is reality about us in the moment. It is not the final word on who we are, and more precisely, who we are meant to be.