What do you do when you lose your patience?

Tonight was a tough night for me. Mom was cleaning the kitchen and wiping the dishes. I couldn't make her stop cleaning. I could hear her chest breathing very hard and she just refused to stop. I fear that she will fall down or even have a heart attack. I yelled at her. I cursed at her. I just picked her up and placed her in her bed. I picked her up three more times and she just got more stubborn. Mom was stubborn before her dementia but now she is even worse. I've been taking care of mom in the evenings by myself for almost six years. I am tired. This is not my mom and I am not me. I have no relatives or immediate family to help me out. My daughters are off to college. I do have three caregivers given me relief during my work hours but I've lost it. I just went outside and yelled at the top of my lungs. Do you have any suggestions?