OK.. WOW.. He definitely has some issues.

No offense, but the Thanksgiving trip sounds like a bad idea. He will push for sex (if he's truly an addict) and you will have a miserable time.

Not to mention the fact that he has isolated his family with all this stuff... how is the family in regards to you and S?

Not sure what others would recommend, but if he's talking about hitting a lawyer and filing tomorrow, I'd excuse myself from the trip up north.