I think not only his parents, but also yourself spoil him too much. Because you have paid for everything, why he needs to work so hard?
I also earn a lot much than my c6. But he must share at least 1/3 of the expenses (usually 50/50) even if he is unemployed. So to force him to take responsibility.
You better keep more money yourself and don't let them know, esp. your in-laws and c6. Just tell them you're poor and have no money.
Ok, understood, that's the 'attitude' problem. It's very hard to change someone's attitude, esp. he is nearly 40.
But may I ask when he needed to find another job, did he resign himself or fired by boss?
He didn't find it a problem, because he is working in a 'hea' company (I've seen a 'hea' company before, everyone is just like that). If he can find a new job, that means he is quite clever actually.
I think it's just his work attitude is different from yours. Some ppl think needs to work hard, someone may think just take it easy & relax. So long as he pays you enough $$$, then that's ok. But if not, then you should ask him to find a higher pay job. For a higher pay job, usually ppl there may be more hard working.
Just like your son goes to a bad school, easily be influenced by others to be lazy.