Grew up in and around Baltimore, and as kids do, took what happened including crime for granted. Then moved to the bucolic (by comparison) delights of Ann Arbor, and then was dragged up here to Toronto by my wife's career which was better than mine. Toronto has a crime rate most if not all American cities would dream of, but as I became used to this (it's now 32 years, I'm old) I too became outraged when an abduction and murder and then another murder occurred in what we considered our neighbourhood, though it was about 12 blocks away.
Crime is like lightning, it really does strike anywhere. Sure it hits hilltops, and particularly hilltop trees more often than it strikes on the flat, but still, it strikes anywhere, at any time. What you do is you let yourself calm down for the next couple of weeks, and then review that this was essentially a new occurrence in your neighbourhood, and that over the last few years it's been pretty good, and according to the laws of averages, it's likely to continue to be pretty good. That doesn't mean, you may not suffer a double strike. They do happen, but over time things tend to even out.
With regard to the lightning metaphor. Hilltops are high crime areas, usually run down and racially fraught, the flat is everywhere else. Also like the lightning/weather metaphor, there's little you can do about it. The police will be feeling the heat, and I do suggest you contribute to that heat in as productive a fashion as you feel comfortable with, "The squeaky wheel ..." and all that.
Just remember that your feelings of contentment before this were not illusory, they were true. And time will heal
I shook for a month after I was broken into in my apt near the University, but it all calmed down, and eventually I felt okay, and back to normal, but in some ways, it never leaves you entirely. It recedes into the background farther and farther, or further and further, and just becomes part of life.
Best of luck, and remember the good, not the bad.