Is this emotional blackmail/manipulation, or am I just a bad daughter?

I’m living with my 81-year-old mother now, which family thought was best, as my dad went into long-term care year last year and won’t be able to come home. I’ve heard before that your parents eventually become like children again, but I never thought my mom would stoop to such tactics as described below. She has started acting like a spoiled child, who throws a “tantrum” is she doesn’t get her own way. I have tried to take all this with a grain of salt, as I realize people’s mental facilities often decline as they age, but at the same time I am having a really hard time dealing with being treated like this. Here’s the situation…

On Friday, even though she had already been out several times in the morning and was noticeably tired, my mom went out again in the afternoon to pick up her prescriptions. Seeing how tired she was, I suggested that maybe she wait until the next day (she was not yet out of her pills), or that I take her later in the evening. She was fine and insisted on going herself. While out on this errand, she ran her car into a pole at the shopping center. She herself was not hurt, but the car had some body damage. It is at the body shop, but will be there for a few days while it is being fixed.

Problem #1: When all this happened on Friday, I offered to take her by my dad’s facility Monday morning to visit with him and for her to pay the monthly bill. She seemed agreeable to this, but when we were talking Sunday night and I told her I would like to go at 10 a.m. the next morning as I had other things to do that day, she threw a fit, saying she didn’t want to go until the afternoon, and that she didn’t know I wanted to go that early. I reminded her that I had told her I would take her Monday morning, and her reply was that she didn’t know we were going to leave that early (10 a.m.?) She became very unpleasant but I stuck to my guns and said either we would go at 10 a.m. or she would have to wait. Monday morning she was back to her usual self. We didn’t go to my dad’s, as she still didn’t want to go in the morning, but I spent the better part of the morning arranging to have her car towed to the body shop and calling the claim into the insurance company. They offered her a rental, which was included in her policy, but she turned them down.

Problem #2: My mom was worried that she wouldn’t be able to go out and pick up some essentials this week while her car is in the shop. Since I have an extra busy week, I told her I would stop one day and pick up what she needed, which amounted to milk and bananas. This morning. when I came downstairs, she started going on and on about how the car was maybe going to take a while to fix (which might be true, but we really don’t know if it will take that long), and how was she supposed to get done everything she needed to do? When I asked what she was worried about, she mentioned grocery shopping. I reminded her that I would pick up what she needed, but then she started to insist that she needed to go and be able to walk around the store.
(My mom walks extremely slow and it takes her forever to shop.)I told her that I just didn’t have time this week, but I would pick up whatever she needed. She then started making ridiculous threats, saying she was going to walk to the store (which is 1.5 miles away. She then threatened to call one of my siblings and ask them to help, and I told her to go ahead. I let my sister know, ,and she’s going to take her shopping, but I am tired of the games. Every time she acts like this, she calls up the other family members and complains about me.

But…is it me? Should I be more accommodating to my elderly mom, or are my feelings justified?

I am just so tired of the manipulation.