There's always been nutters and mass murderers, just more often with a terror motive since about the last 5 years. A few years ago every other headline was to do with a terror attack. Read into it what you will.
Isn't there an element of over reporting? I am sure that around the world there are daily occurrences of multiple homicide but we don't hear about them all. On a slow news day the press need to fill their doom and gloom pages with something. On another day this story would go unreported in Britain.
On the other hand, take a look at the suicide rates - maybe too much ‘happiness‘ isn’t that good for people. As for your reminder - if you don’t like it here then there are plenty of other places that may suit your moral standpoint, your choice.