Only thing I can think of is that the author was a guarantor on the mother’s debt. Which I suppose is possible. Even still though I don’t understand why the house would go to the state.
The book she mentions is pretty old, but the situation with her mother she mentions is current.
The house going to the state could be due to Medicaid reimbursement. But I share your general frustration that when such details are glossed over it tends to propagate myths (two, in this example). If this is what happened, a will wouldn't have helped. Deeding over the house while keeping a life estate or putting it into a formal irrevocable trust, before the lookback period, could have.
The book she mentions is pretty old, but the situation with her mother she mentions is current.