I'm the oldest of 5 kids and the only one who takes care of my mother. She is and always has been difficult to deal with..now she screams, yells, at me over nothing..my siblings never see this side of her..it is depressing me. I don't know how much more I can take.
But, I'd consider that if she's always been difficult, she may be much more so now, depending on what is causing her agitation. I'd explore other options for her care. Not everyone is cut out to be a hands on caregiver. And, some conditions progress, what if she becomes more challenging to care for? I'd read a lot about what the cause is and explore my options. Perhaps, other family members can step in and see for themselves what is going on.
Where is she living? Have you had a " needs assessment" done by the local Area Agency on Aging? They can help pinpoint your mom's needs and what help she is eligible for.
It sounds as though your siblings have done a good job at setting boundaries with a toxic parent. Can you do that as well?
Do you walk away when she screams? There is no excuse for a parent to verbally abuse her adult child. None.