Repeating things.

The other day, I was having a telephone conversation with my husband, part of which my mom overheard. She never made a comment to me, but when my son was here, she repeated what she "thought" she heard to him. The conversation partly involved him, but she got the conversation wrong. I did call her out on it, that what she was saying was wrong, that she jumped to conclusions about what it pertained to, and that she only heard part of a conversation. She only heard my part, and not my part entirely. It looked like I was bad mouthing my adult son, which was not the case. I then, had to explain the conversation to my son. I felt like she was being manipulative. When I first pointed out to her that what she was saying, was not what I said, she actually, was confrontational. She said, I didn't hear you say that Zach bought the child such and such? I said, No that's not what you heard. I am so frustrated. I really wanted to tell her she shouldn't repeat what she "thinks" she has heard. She does this in a one on one conversation. You start to say something, she jumps in and completes your sentence with what she thinks you are going to say. When you tell her what you were really trying to say, her mind locks onto what she initially thought. It drives me nuts.