I am writing to apologize for the unfair treatment that I have subjected you to. I understand that it was wrong of me to act in such a manner and I take full responsibility for my actions.
I know that I have not been treating you with the respect and kindness that you deserve. I am sorry for the hurt and frustration that I have caused you. I want to assure you that this kind of behavior will never happen again.
I understand that I have been unprofessional and inconsiderate in my dealings with you. I have not been taking into account your feelings and needs, and that was wrong of me. I apologize for my lack of empathy and understanding.
I want to make it clear that I do not condone this kind of behavior and I am taking steps to ensure that it does not happen again. I am committed to treating you with the respect and kindness that you deserve.
I realize that my apology may not be enough to make up for the pain and frustration that I have caused you, but I hope that you can find it in your heart to forgive me.
Once again, I apologize for my unfair treatment of you and I will do everything in my power to make sure that it does not happen again.