Just want you to know that you are not alone... When I went to visit my mother last, I took her some raspberries and when I sat down I entered the "flee" mode. I got up and ran. I am sure she was surprised thinking I would visit for a bit. It was an anxiety attack!
As with any mother/daughter relationship, we have some issues. Afterwards, I have to focus on breathing to get through these anxious periods. I do feel it helps if I just do it and be patient with myself. (That is why I am always saying to take a deep breath, and then another, and another...). I know that I quit breathing altogether when I am stressing.
I agree with onelife that it would help if you could get assistance on paying the bills for your mother's care. I don't know if that is possible where you are but perhaps you could set up billpay through the bank which might ease your burden a bit.
Keep the faith Skwirl! You are stronger than you think and have such wonderful insight. Keep looking at the blessings in your life and stay strong...