No Granite. She is not saying she purposefully doesn't say anything with the intent of upsetting you. She is saying she recognizes that you interpret silence as anger. Two entirely different things.

T's very normally sit quietly and wait for us to gather our thoughts and speak. That is not mean. She is just allowing you space to gather your thoughts and communicate them to her. She's at a catch-22 with you. If she speaks, you often interpret her words as anger, but if she is silent you do then also.

It sounds like you stopped hearing her when she said the part you quoted. My guess is she was trying to help you see a similarity between how you react to her and how you reacted in the store situation, but you took her observation and ran with it as evidence that she's sadistic rather than truly hearing her whole message.