When is enough? Going crazy.

I am at the end of my rope. Yesterday I wanted to crawl under a rock and have another fall on me. I take care of my mother who has ESRD and is just mean. We are unable to make ends meet financially and I take side jobs which requires a LOT of computer work. Friday 13th I get caught up in traffic which was backed up 20 miles one way and 10 the other. If that wasn't bad enough my IPhone died. I NEED my phone, it helps me make money. And the money I make equals to about $3-4 an hour by the time you add driving to/from, gas and time on the computer. It's the only thing I can do because I have to also take her to/from dialysis. My computer is slow as Christmas and isn't working right so it takes even longer. So the other night at 11pm I am working hard to get reports entered into the computer or I don't get paid if not in by midnight. My mother starts yelling because she wants milk. At 11pm I have to stop what I am doing to go get milk. Yesterday I again am working hard to get a bunch of jobs completed or risk loosing quiet a bit of money. Not that much but anything is a lot to us. I lost an SD card and was digging through the trash trying to find it. I was at the end of my rope. Now I risk not getting paid for jobs but also having to pay for the SD Card. I was in tears. Sounds like nothing but sometimes the slightest thing can send you over the edge when you have had enough. And that almost sent me over the edge. The thoughts of just ending it all really came to mine. I suffer from serious health problems which can never be fixed. Back pain, neck pain, hip pain, knee and ankle pain. It's all over my body from where I was in an auto accident a long time ago. 40 surgeries later I am somehow still going. My mother cries at the thought of having to go into a nursing home because she thinks she will die. In her health she is going to die soon anyway. But she is so mean and she knows what she is doing and saying. She has always been this mean to me. I have 3 brothers and 2 sisters and get absolutely no help of any kind from them. They don't call or visit. My mother picks the worst times to start her tantrums. When she does it throws me into a bad mood and it messes with my jobs. I can't get into the mood to do them. When you are hurting physically and then just left a fight you can't get in the frame of mind to do anything. Things haven't always been this bad and when something went wrong I was always able to pull a rabbit out of a hat and fix it. She thinks I can still do that and I don't know why. I have told her that I have no money. She doesn't care. She wants what she wants when she wants it. I hate to put her in a home but none of the rest of the family is going to take care of her. But I can't do this anymore. No one thinks of the caregiver especially her doctors. Ending it would be so easy. I am so tired. Her appointments at the dialysis clinic were changed and moved forward by a half hour. She is still late. She says she doesn't care. She is always late and wants me to take her to the drug store and to go get a biscuit. I told her "mom, they are going to get upset with you if you are late after they give you an extra half hour and you are still an hour late." She yells and tells me to just take her on to the clinic. She pitched another fit.. I don't know why I am posting all this, perhaps in hopes someone else (sorry to say) has gone through something similar. I am sick of all this. I love her but don't like her at all. She manipulates me to the point I would do anything. And worse I know she is doing it. My thoughts are all scrambled I know. I just don't know what to do. She is paranoid and thinks I am trying to poison her. She thinks I do things like talking to my siblings and I don't. I tell her that it hurts and upsets me they don't bother to help and guess what, "it's all your fault". Yes, it's all my fault that my siblings don't bother to help us. EVERYTHING is my fault. I am a Christian and really hate the thoughts that go through my head. I think sometimes that I wish she would just move on. That is so bad and I know it. I should never think like that. I feel that I am going to be punished for thinking this way. I just don't know what to do. Everyone says "Have a family meeting". LOL. It would be a cold day when that happens. They have no interest in being part of her life nor mine. They are afraid if they associate with me they will have to do something for her. In the meantime I am trying to earn money to get the cable bill paid and gas to take her to/from dialysis. She doesn't care how things get done as long as I get them done. I am so tired at night when I go to bed I am sound asleep. I don't sleep well due to the pain but I do sleep due to the fatigue. I could lay down now and never get back up. Wishful thinking. Any comments or suggestions welcome. I am so tired