What is guilt as it relates to faith? How can we forgive ourselves for something we regret?

​The connection of guilt to faith is indirect. Guilt is a relationship to a law; either a subjective one -- I feel guilty, or an objective one -- I am guilty, whether I feel it or not. The main concern, as far as Christianity is concerned, is objective guilt. Because of sin, every person stands guilty before God. Faith, then, is a way, the only way, to alleviate that guilt. By placing faith, or trust, in Jesus Christ, our guilt in relation to God’s law is removed, graciously, absolutely and completely.
The idea of being able to forgive ourselves, a very questionable pursuit, pales in comparison with the need to have the holy God forgive us, something that is freely available – through faith.