I am so sorry to hear about your mother. It must be truly difficult for you at this time. Stress can play havoc with your blood glucose levels. It is also very possible that your high BG levels may play a part in the symptoms you are experiencing.
I have no experience with this type of stress, and my stress busting techniques are limited to beating 10 tons of doo-doo out of a stress doll and separating myself from the situation, neither of which sound entirely appropriate for you at this moment.
Is there someone who can take over your care duties just for a short while, while you take some time out for yourself? At the very least I would imagine you need some time to relax (at least for a while).
Regards, Tubs.