There is a difference between feeling guilty and being guilty. People may suffer from a sense of guilt that is unwarranted. As Tony Ward (not the rugby player) points out:
When our consciences are oversensitive, or inaccurate, then we can end up emotionally whipping ourselves with false guilt. The cause is usually that our consciences have been overly conditioned by our parents, our society or the type of education we received. Legalistic homes and churches which put an undue emphasis on rules and regulations, dos and don'ts, tend to breed people with hypersensitive consciences and resultant emotional damage.
A person whose parents were quick to condemn other Christians who consumed alcohol may feel guilty when having a drink, even though their firm conviction may be that Christians are free to consume alcohol in moderation. A son or daughter who had a parent that regularly claimed they did not care for them could later feel guilty having that parent admitted to a nursing home, even though they are acting on best advice. A child runs onto a road chasing a ball, the driver who hits them feels guilty even though the police said it was not their fault. A teenager fears that they are somehow to blame for their parents' divorce, even though the parents had been fighting for years. A member of a disapproving church feels guilty partaking in innocent hobbies they enjoy.
How do we help people suffering from unwarranted feelings of guilt?
Firstly, by being patient. It might take a person a long time to unlearn years of disapproving parenting. If they have a distorted view of God it may be a struggle for them to accept true beliefs about his character. If the consequences of an action were serious they may find it difficult to let go and move on. While they may agree that their guilt is unwarranted it may take time for their feelings to catch up with the facts. They might make progress in letting go of unwarranted feelings of guilt and yet may relapse at times.
Secondly, we need to be willing to listen well. They may actually know that their sense of guilt is unwarranted. As they talk through the issues, with someone who shows them understanding, they will be assured and grow in confidence.
Thirdly, we need to help them in trying to separate emotions. For example they may need to learn to distinguish between sorrow and guilt. While it may be right for them to work through some emotions false guilt serves no good purpose.
Fourthly, we may need to allow them to confess. While we may be sure that their sense of guilt is unwarranted they may remain unconvinced. In such situations we can encourage them to bring their feelings of guilt to God and remind them that God readily forgives his people.