Can anyone help? I've realised my list of books I have read this year is incomplete and that just won't do.
Spoilers and description of horrible scenes ahead so tread carefully...
It's a detective thriller. I remember it has a helpline at the beginning or end due to the graphic descriptions of murders. Here goes...
There's several murders through the book. The first is a girl living alone. There's a texting exchange where she realises the killer is in her house. She is found hanging from a hook. There's some sort of note/line from a poem but I can't remember what it says.
Another murder is a young guy and there is something involving him being mutilated with lobsters(!). Again, a line of a poem note left.
Hazy after that but it is eventually worked out that there's a connection between the victims that their close loved ones were all in the same class at school and they bullied a girl who killed herself. The killer turns out to be the mother of this girl, seeking revenge. The end involves her trying to escape on a plane and the detective getting shot.
There. That's what I remember!
Any ideas?