I could have been the author of what you have written above! (I wonder if what I write now is what you could also say)....I would arrive to see my Mum with her telling me about her bowels/bladder/or that she had a job for me to do...not "hello nice to see you!" Most days I could just let it go but sometimes it was hard having done a full day at work then coped with a long drive to visit her!
My siblings for differing reasons left it all to me, I did what had to be done, when it was needed, I gave up the odd glass of wine as I never knew if I would need to drive and I gave up a lot of my hobbies and activities as I was just too tired. Started making errors, gained weight and forgot to go to the dentist (found that out when the dentist ticked me off as I hadn't been for over 3 years....
I slowly became less of a daughter and more of a carer, advocate and took over the finances and social arrangements for Mum to help her maintain contact by phone and with visits from her friends and family.
Her moving to a nursing home, as I have said on other threads I have written on the forum, was - with hindsight - something I should have done earlier...but it is a tough decision - and brings it's own difficulties.....
BUT it meant I could sleep better knowing if anything happened someone was there for her, and for a lot of 'incidents' I didn't have to do anything at all...eg a minor fall they dealt with and I could phone her, and visit later as planned. The chores went!!! (washing/cleaning/food etc)
I know how hard it is. I didn't look after myself - Mum's needs always came first - and when I was exhausted I knew I wasn't being a good carer! (or safe in the car - driving to see her)
On a positive note - being the only sibling doing what needs to be done, meant that I made the decisions when things needed to be decided!
Look after yourself and say "Yes" to anyone who offers help!