Simple solution to your problem, get rid of your business.
You shouldn't even be in business if money is tight, the goal to a business is to have overhead business costs that you can afford while still having emergency funds saved incase something happened.
You don't have that. Your business costs is draining your income making you "tight but doable" in terms of income, that's the wrong way to think. Do this last business venture, sell the truck, and don't do any other business venture again until you have atleast $50,000 in cash saved up. THEN you come back to it.
Also, your parent's debt are not your own. They need to fix it themselves and learn some type of money management. The more you help them, the more you enable them since they now expect you to be there to help out with their money problems.
If it's one thing I learned through the years, it's never ever get involved with someone else's debt no matter how much you love them. The only reason you'd ever get involved is if their debts are minimal (aka $20,000) and you can afford to help them. THAT'S IT.