One of the first things we all need to do spiritually is to learn to love ourselves as we are. This is easier said than done, unfortunately.
Perhaps we have been warned so often against becoming egotistical or narcissistic, that we think we are doing something wrong if we feel good about ourselves.
Perhaps we have had instilled in us the idea that humanity has fallen from a state of perfection into a state of total corruption, so we can’t lay claim to anything good in us. Even our desires and dreams are to be considered sinful.
If we can see that we are simply evolving beings, along with every other being around us, then we will not call every bad choice a sin. We will understand that mistakes are part of the way we learn. We can let go of ideas of perfection that can only condemn us.
When we let go of self-condemnation we can evaluate ourselves and others more on the values that are held rather than the deeds accomplished.
To let go of past guilt and shame is not to forget the lessons learned from them. A scar may be a healthy reminder to stay away from fire or sharp objects. If we forget the ways we may have caused suffering for others, we will not grow into kinder and more thoughtful people. Learn the painful lessons, then move on by loving yourself, scars, warts and all.