I see it this way:
The guy had a major stroke that left a lot of damage and was not allowed adequate time to rest and rehab. The dems are using him as a pawn to hold on to their own power. Horribly, his own wife who should be protecting him when he is most vulnerable and needs her the most, is using him as well. They prop him up and thrust him into an impossible situation that he is incapable of handling -- interviews, committee meetings, a debate, and just simple everyday one on one communication. Being abandoned and used and under constant frustration with inadequacy, who wouldn't be in despair?