Oh Hops, you're amazing

. I'm struggling as I type this. My Nmom is here visiting and it took less than 24 hours from picking her up at the airport for her to start the N abuse. My boundaries have controlled the majority of her behavior but her N is so deep that it is leaking out all over the place. She can't help herself.
I don't want to regret letting her in my life like this and allowing her behavior to ruin my day(s), which it always does. 20 years from now I don't want to say, "oh I should have done..." or "I wished I hadn't let my Nmom do this or that..." I want to be in control and I feel like I've lost control, even today as she's in town shopping while I'm home taking care of some things, I feel like I'm being strangled.
Short story that sparked my anger:
Nmom left a bottle of pills (blood pressure/heart/high cholesterol or what not) on my bathroom counter within the reach of my 2 year old. My husband saw them and moved them to the top shelf of the wall vanity. Nmom saw them there the next day and took them down and put them in a bigger bag of pills she had and placed the bag on the floor by the toilet, again, within reach of my 2 year old. The next day, I calmly told her about what my husband did and that I noticed the bag on the floor-- both things being a big NO-NO in our house, right? Well, as I was calmly telling her about how my husband found the pills on the counter and placed them on the top shelf of the wall vanity, she said she didn't see them at all and didn't know of them, etc. Well, she took them down herself, right? I said to her that if she took them down herself from the top shelf, then she
had to know of them, that they had been moved, etc., right? Nmom went nutso-freako on me...(you see, I cornered her emotionally and she lashed out, typical of N's) She then said she thought I was talking about individual pills and that I didn't have to accuse her, that she "never said that I didn't know of the pills", etc. WHAT???
She contorted the situation and mixed up the conversation so badly that she wasn't making sense. She began to yell that I put words into her mouth, that she never said this or that. WHAT THE HELL WAS SHE TALKING ABOUT?? I very calmly said, "no mom, I would assume that if you took the pills down yourself that you would know something about them when I told you that my husband moved them to the vanity, but you said you knew nothing about them."
She kept repeating, "I never said that I knew about the pills, I never said that I knew about the pills!" This was the complete opposite of what I was saying!!!!!!!!!! She yelled at me and an argument ensued....blah, blah, blah.
I don't get it.
I don't get it.
I don't get it.
I'm pissed right now.