What causes depression?

I don’t have it. I am not print either. I think I get back on my feet too soon and am a bit forgetful , so forget heartbreaks easily.

But my mom has a major depression annd has to be treated for it lifelong and I know how much it can affect your life… What causes it? Why do some people get it and some not? Why not me?

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4 mo
I don’t know what I meant with “I don’t print either.” I suppose I meant I am not prone to it.
What causes depression?
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