it doesn't matter what you do for a living - its your living.
i would tell DH he's got 30 days to empty that studio and get back to work on it or you're hiring someone else to do it for you.
i also earn my living from this art and my DH would never take that attitude. its my career and helped us buy 4 homes, 3 cars, a boat, and a motorhome - all this with zero consumer debt.
just because its art doesn't mean its not allowing you both to have the finer things in life and he needs to finish this space so you can grow your business and your bank account.