First off I can relate to your worry about spending time with your mom, worrying if she is safe, trying to hold a 'normal' family together at home and then of course to take time off and meet the financial level that you may need to carry on.
I have found that I am just plain bone tired. When I daydream I think of laying on a beach away, far away from anyone that needs anything from me; I have been running on cortisol for so long. BUT I am choosing this because it is important to me to have my dad at home as long as he can. He deserves it
I have siblings but they are so uninvolved and I had tried to call them to vent and asked for some help but they just turned around and complained that I am too moody and should just take good care of myself. They will come for a 15 minute visit, complain about the 'fridge being not too clean' and then leave! Easy for them to say. I guess one thing I do know is that this too shall pass - that this time is a particularly difficult one for us in our lives and one day it will be over and in our hearts it will be so meaningful to have done our best to make this time mean something. Anyhow hope that helps