I did get my Ritalin refilled. It helps a bit. Thanks Mopey and Fuzzy. Sooner or later, something's gotta give. I hope it isn't my sanity. I tell myself it would be better to scale back my involvement gracefully, then just become a wreck who can't cope, and then others have to take the situation in hand.
My options seem to be all or nothing. Seeing this man through to the end is like trying to get to the mountain top and plant my flag, saying "I completed what I undertook." I'm just slogging forward now, one foot in front of the other.