You need not find any excuses for your husband’s behavior if you are to forgive him. Forgiveness is not based on finding excuses, but instead is based on seeing his worth, not because of what he did, but in spite of this. Further, try to see his inner world. Is he wounded in any way? Confused? Do you see a human being rather than someone who is less than human? These kinds of perspectives can increase empathy and foster forgiveness.