@Helen10 you haven't failed ... dementia is an impossible task master, it robs the person and their family of so much, and messes with our minds so we can't see the wood for the trees, forests, logs planks and goodness knows what else
we are each of us only human and can only do and take so much, yet we expect more of ourselves, then feel bad because we can't meet those impossible expectations
it hurts so bad that we can't fix our parent and make everything good for them
the horrible, sad, crushing fact is that dementia will take everything and chew us up
please, cut yourself some slack ... you are human, you're a caring daughter and your mum of old would be proud of all you have done for her and that you are standing by her and your dad
I know this may all sound trite and of little comfort right at this moment ... just maybe trust us that you will come through and be able to see how much you have done rather than what you (and everyone) can't do
I hope you get some sleep tonight