I was thinking just that - even if this isn't what actually happened - the fact that if he dies or goes to jail the wife would get the house and probably much more (any known savings/investments, life insurance if there is, etc) is alarming - to say the least.
If on the other hand he didn't buy the house (only rented), didn't marry her, and all assets were kept out of Thailand - her motivation would be to keep him as safe as possible.
But to sum it up, as you said - if she knows you're worth much more to her alive and well than.. uhh.. not.. chances are you'll remain that way.