Krimis - who needs them!

Last night I started reading a thriller I borrowed from a (male) friend, and I had to put it down and read a few calming pages of P.G.Wodehouse before going to sleep. I I felt so upset and revolted by it. It was all about snuff movies and female torsos littering Brighton Beach, and of course unlovable psychopaths behind it all...
Whatever happened to genteel whodunnits? Country house mysteries? Humour?
I can live with a bit of suspense, even a bit of illustrative sadism, as shown by Minette Walters, or a bit of nutcasery so lovingly described by Ruth Rendell. But for the life of me I can't see where the entertainment is in reading stories about raped children, dismembered women, cruel and sadistic murderers who torture people before burying them alive? Because - am I wrong in thinking thrillers are meant to be entertainment?
The author of the Brighton Massacre is someone called Peter James, by the way. Maybe he was relying on people thinking he was PD James.
I think I might have to re-read Agatha Christie, that's what I call NICE murders.