Well, if you find that you don't remember much about the plot or characters after reading, chances are you're going through it too quickly. Maybe try to slow down and savor the experience.
It's quite close. The anime of Inuyasha largely adheres to the manga, with only a few minor differences that don't significantly impact the main plot or characters.
Well, it could be about a story where the events are so relevant to the main character's home life that it makes them feel uncomfortable or forces them to face things they've been avoiding. Maybe it involves family secrets or events that unfold right where they live, and the characters have to deal with the consequences in a very personal and intense way. For example, it could be about a mystery that is centered around the family home, and as the story progresses, the main character discovers things about their family that they never knew before, and these revelations change their perspective on their home and family forever.
I'm not familiar with the specific 'too close to home novel' you mentioned, so I can't say who the author is. It could be an indie author or someone relatively unknown. You might want to try searching for it in a library database or a specialized book search engine to find out more about the author.