Does he have family with him to do the day-to-day stuff? The bill-paying, the shopping, the taking to appointments?
Otherwise you'll be doing the bill-paying from a distance, shuffling back and forth to fight fires and generally marshalling his friends (if willing) to fill in gaps.
Emotional support, too, of course. Listen. Support his partner/children (if there.) Listen to them. Never give advice to them. Everyone gives advice; hardly anyone listens.