i'm all for asking what he might want for dinner and letting him choose the meal one or two nights - providing it doesn't mean you dropping everything to drive to the next town or him waiting until after you are half-finished making dinner.

i'm guessing you aren't charging him room & board or anything.

just a tad ungrateful and inconsiderate to cut down every meal you make.  if he doesn't want to eat it then no biggie, let him go hungry.

for the socializing - i'd give him the benefit of the doubt.  maybe he's just not comfortable striking up a conversation with a stranger.  and i doubt very much that had anything to do with his sudden extreme thirst unless getting hammered is the only way he can deal with an awkward situation.

and if he reverts back to the rude, inconsiderate houseguest i suggest going out and finding that horse that kicked him in the head and enlisting it to kick him in the keester

whatever his problems are it doesn't give him a right to take it out on those around him