"At this point I can't even buy a cheeseburger without being yelled at," she said. "I'm starting to resent any money conversations. Is there a reason why this should be their business?"
It's not appropriate or usually effective to yell at a grown person. But maybe her parents are yelling because they feel guilty that they didn't teach her how to manage her money. Perhaps it's because they care or are worried she may never get back out there on her own. Maybe they are frustrated because they haven't seen any financial progress.
How would they know if she had changed if she doesn't show them the proof?
So she should tell them exactly what she has been doing to straighten things out.
Pull out the bank statements since moving back home and let the parents see that she is balancing her checkbook. Show them that she is no longer relying on debt to live beyond her means. Let them see that she is building up an emergency fund, even while you are paying down your debts.
Let them have a look at her budget, which she most certainly should have.
Show them her debt payoff plan. And, update them every time she makes a significant dent in that debt.
She should be -- needs to be -- transparent, because by sharing the information with her parents, she may win back their respect and hopefully put a stop to the yelling and hovering.
Should this be their business?
Yes, I think the financial well-being of your children should always be your business, whether they are living with you or on their own. I know I'll be advising my children about financial issues even when it moves from my full-time to part-time job.