How do you guys who live in the country handle it? (Please read description...)

I am a city girl. Never been in the country or out in the wilderness. Never caught a fish or went hunting. I'm use to sounds of sirens and "fireworks," music, cars, etc. But this morning I heard the neighborhood dogs going crazy. Something wild was in the dark. For the first time I heard an animal get killed. Whatever it was, killed a cat. 😢 How do I get that haunting sound of this cats last cry out of my head?

It'll pass.
It always passes. 
I've heard that sound too many times to even care now.
Although I would always help if I could 

Awe Yin I’m so sorry!  It’s never a good sound hearing another animal get killed . I still cringe when I hear them fighting but it’s a part of life that I’ve always known about.

I read somewhere that some wild cat ( cougar) maybe has been spotted roaming around California neighborhoods. Is that your area?

I live in the city.

Same way but less intense than you.

Time passes. Sometimes you'll have to carry on

Very sorry to hear. The closest I've heard to that was the odd cat fight outside, but that doesn't end as bad as your situation. Whenever I see/hear something bad that I can't seem to forget, I just take my mind off of it by going out, or watching something. :-)