Since The Woman in Black is more or less set in the middle of nowhere among bogs and fogs, it makes sense that a lot of the book is basically a how-to guide on being scared and alone. In the book, Arthur finds himself literally separated from the rest of society when he arrives at Eel Marsh House, which is cut off from the mainland when the tide rises. And then when he finally gets back to London and a semblance of normal life, he finds himself alone even with his new family—since he can never share with them the horrors of his youth. Do you think he's starting to feel some more sympathy with Jennet?
In the book, Eel Marsh House represents both physical and emotional isolation from the real world.
Jennet can't find peace as a ghost and continues with the cycle of alienation and isolation even in death.