The title is a lie, perhaps. For the house on its own is not haunted; it is occupied. Whatever walks there walks alone but it walks there, it was there first, it was there from the first.
And it does not want new occupants. I say that all the banging, all the terrifying noises, the ghastly visions, are attempts by the house to drive its intruders away. I say that as the house sees it, it is haunted by visitors.
And yet the House does not try to exorcise its visitors as one would a ghost. It does not drive them away plainly and honestly, in the manner of Sentinel Islanders or stern security guards. It traps them there each night and torments them with terrifying visions. That is not harsh justice. It is cruelty.
The house is not sane. But it chooses to prolong the situation. It chooses to continue its own suffering as it continues the suffering of its invaders. Should I then forgive it?
I woud have to know if the house has any ability to end the situation quickly. For if it has only so much physical power, then it would not have the force necessary to physically sweep out invaders. In such case I would say that the terrifying visions are necessary, because the house has no other way to convince people to leave when they are determined to stay. And it takes time to break someone's mind, so there is no way to do things quickly. But if the house can sweep people out as easily as a broom to an ant, then the house was in control all along, and has no excuse for its actions.
Yet is it in control even then? The house is not sane. Yet I have heard of no real mental illness that inspires people to break the minds of other people. There is no such thing as Criminal Insanity. The house cannot make that excuse. The only excuse the house could have is a lack of control over the situation. If the house and the invaders were equally matched in will, then I can offer sympathy, for the sake of lamenting a situation that could not have gone any other way. If the house held more power all along, then I will offer no sympathy, but call the house cruel.
Whatever the case, whatever walks there walks alone. It will not let itself be connected to the wider world. Any attempt will only cause pain for all involved. Let it be so. Let it alone.