Well, in this case, the bad news can be the good news.
Much like OP's MIL giving the silent treatment is less a punishment than an appreciated respite - OP and her husband can use the family's perception of "use of the vacation home" including any time they step on the property *as* the reason for never visiting there again.
"As we told you before you bought the property, we aren't interested in using it, nor working on it. Now it has become clear that when we try to visit you there, everybody views it as our use of the place, and obligated to do work - so, we will skip any use of the property. Let us know when you would like to visit us anywhere *except* the vacation home - you may enjoy a break from chores!"