As I write this, some 60 comments have been posted; I have not read all of them, so this might be redundant.
There appear to be two separate problems here.
First, your husband's psychological makeup, specifically his willingness to take advice from his father, and more generally his "other-directedness," willingness to be unduly influenced by others. All of us have a certain amount of this; it's why we don't go to work in filthy clothes, don't curse the neighbors for no reason, etc. But your husband seems to carry it too far.
Maybe he could learn to say, "Sorry, Aunt Jane, even if we needed the money, which we don't, you're not offering even close to minimum wage. If you can't afford to hire a painting company, we'd be happy to give you some financial guidance."
"Gee, Dad, how's your latest bankruptcy procedure going?" (Yeah, that's quite snarky, isn't it?)
"So friend Fred, you just got back from a cruise. Tell me, where'd you get the money for that, since you just moved into a new house you can't afford?"
Second, there's his anxiety, his worrying that suddenly the bottom will drop out of everything and you'll both lose your jobs, and the cars will fall apart, and the banks will close, and the gummint will decide to raise taxes, and the sun will expand suddenly and wipe out the earth. And then things will go really bad.
The answer to both of these might be a bit of talk-therapy. Not with you, but on the one hand with a CPA and/or a fee-based financial advisor who could look at your numbers and say "You're doing fine." And on the other hand with a psychologist who could help him come to terms with the family dynamic and his reaction to it.
Of course, he isn't the only one who has these difficulties -- as a few hours of reading this subreddit will demonstrate.