Do i need to sign any documents of acknowledgement with a lawyer to fire them?

I need a question answered! I recently hired a lawyer and signed a retained, no monies given and things went sour before we started so i basically told her via email, due to personaility indifferences, i can't have her represent me so now she wants me to sign an aknowledgement but i don't feel meeting her face to face is a good thing after many things that were said.. I live in NYC and my question is this, Can't she just send out a letter stating the firm is no loonger representing me or can i write one to that affect and send it via certified mail and be done. She does have some paperwork of mine but it just isn't worth the confrontation.