Unforgiveness can be like experiencing a death.
What is the point of your unforgiveness? Is it because someone hurt and/or offended you? Do they even know that what you did and/or said harmed you? Most likely, they have no idea of the harm that they have caused; forgive them so that your pain does not fester into bitterness and isolation.
When we are hurt and in pain, we can respond in ways that are out of character for us. Most people are unaware of the harm that they have caused. Are you withdrawing from them? Forgive immediately before your love and joy is gone. Your love and joy could be destroyed without you even realizing that it is already gone. You can have love, joy, laughter, peace, rest, hope… You can have it all and when you have a complete surrender in forgiveness. Only you know where to start. Let all the hurt and pain go by forgiving over and over. Forgive and repeat and then forgive another and another until all your hurt and pain is replaced with love and joy.
Those who are closest to you can be the greatest offenders because they matter most to you. Forgive them!