Well when he is pressing the alarm - whether its just for attention, or if its not justified, this is a big red flag he is lacking judgement and is not safe to be living alone and will need a care assessment, capacity assessment and likely safeguarded by being placed in a care home. (It would be more expensive for the local council to arrange a night time carer.) But this is all part of their professional duty of care.
If you have a power of attorney for health and welfare then you would still have to be involved in any best interest decision, but you haven't mentioned this, so I think its not applicable.
You do just need to step back, you are not obligated because you are the daughter to be involved in arranging his care or providing it. You can simply say I can no longer be involved in my dads care. My mental and physical health is suffering. I am not sleeping. My work is suffering. My children are suffering. I am no longer able to be the point of contact for my dad.
Op, I am so sorry this is such a burden on you. The pp above asked you to think about what would happen if you dropped dead..
You are being pulled at from all sides, with so many responsibilities. If you had a breakdown, you would end up in hospital or totally unfit to manage any of this, not your dad, not the calls, not your work, not your kids. How long might it take for you to recover......... Abuse distorts a childs sense of identity, duty and self worth, and those distortions don’t magically disappear in adulthood. We dont feel guilt out of love but from conditioning that made us feel responsible for the patent. Its not really true guilt, you havent harmed him, its that we've been programmed that way from the abuse.
Edited for typos