I am writing to apologize for my unprofessional attitude during our last meeting. I understand that my behavior was unacceptable and I apologize for any distress it may have caused you.
I want to assure you that my behavior was not indicative of my normal attitude or demeanor. I am usually a very professional individual and take pride in my work. On this particular occasion, however, I allowed my emotions to get the best of me.
I understand that my unprofessional attitude was disruptive and caused a great deal of discomfort. I should have taken the time to pause and reflect on the situation before I acted. I realize now that I should have handled the situation in a more professional manner.
I am deeply sorry for my actions and I understand that I must take responsibility for my behavior. I am committed to learning from this experience and I am confident that I can improve my professional attitude in the future.
Once again, I apologize for my unprofessional attitude and I can assure you that it will not happen again. I value our relationship and I want to make sure that I am always acting in a professional manner.