Wow. Reading this makes me angry on your behalf. I agree, you are NOT burned out. You are experiencing the moral distress ANY of us would in these circumstances.
I hope you can find a new position soon. In the meantime, I echo the notion that you continue to stand up for yourself and your patients. It is the RIGHT thing for you to do. If nothing else, hopefully you will leave this unit and those who manage and work in it, with a solid understanding of what it feels like to be called out on unprofessional, unsafe, and unhelpful practices.
By "calling out", I mean - escalating these unsafe situations up the chain of command until they are dealt with appropriately, exercising boundaries ("I can work this, not that", "I can be a sitter for one patient, or I can care for a group of patients that either have sitters or do not need them" -- sitters by the way are sitters bc they are one-to-one). And the CNA who pulled you aside ..... oh my. You are very kind in your assessment of that situation. I would have given her a "professional learning opportunity" right back.
I hope you have some nursing friends in your life that you can talk to about this. What you are experiencing is not normal, not acceptable, and needs to be addressed by someone with the power to do it. That is not you, so I suggest you move on and wash your hands of it at your earliest opportunity.