I just want to leave...

I'm so sleep deprived so if some of this doesn't make sense, I'm sorry. My grandmother is 94 and her care needs are killing me. I have to keep getting up all hours of the night to take her to the bathroom. She refuses to use her adult underwear. She keeps pushing the call alarm in the middle of the night. It's impossible to get rest. I get no rest. They expect me to be damn robot. I love her but damn she's killing me. I catch myself being snappy and then feel like crap afterwards. I'm doing the work of 3 full time caregivers. I'm her nurse, caregiver, cook, housekeeper, yard person. It never ever ends. POA sitting on a lot of money and I get 60 dollars a day. I want to cuss him for everything he is. He's so damn greedy. I'm so angry all the time. And there's sometimes I just don't even want to look at my grandmother. I never get away from her. I had to get up multiple times last night and clean poop from her back, change her clothes, change her bedding. I've never felt less than a human as I do now. I'm so afraid that I am going to just walk out and be done with all of it. No day off or away from her in 3 years. No one comes to help me. No one. I'm a modern day slave. Thus has forever changed who I am as a person. I would never want anyone to do for me all I've had to do for her. I would want God just to go ahead and take me out of this world!!!!