Do I have to grow in character before I am able to forgive? If so, what character traits do you see as important?
This is one of those chicken-or-the-egg dilemmas. It seems to me that as we forgive, we grow in the moral virtues, particularly of courage (as we decide to move forward), humility (as we try to see the humanity in the one who acted unfairly), and then eventually in love, particularly agape love, or that which is in service to others for their sake. Agape love costs the one who loves; it can be a struggle to offer goodness to another through a broken heart. These three: courage, humility, and agape love, I think, are major fruits of forgiving.
For additional information, see What is Forgiveness?