As a person who frequently struggles with depression, I know that life can hurt sometimes. But it's alright because no matter what, we CAN get through it. No matter who tells you otherwise, life is worth living.
There will be many sad nights in your future, sure. However, there are several ways to prevent depression. First things first, make sure your self-esteem is intact. For a lot of people, it's hard to believe that they are amazing because of what others think, say, or do. Well listen here. You ARE amazing. The only person standing in the way of you building up your self-esteem is YOU. I don't know every single person in the world, but I do know that every single one of us has the ability to be wonderful; the ones who don't wield their unique beauty and talents will fall apart. Yet, you don't have to. We're all beautiful people--don't let you stand in the way of feeling beautiful.
The second thing that might help prevent depression is, stay active. Exercise releases chemicals that make you happy! ^D^
Thirdly, read books if you like that! Books are portals to other, happier worlds depending on what you choose to read! Sometimes it can help to go somewhere else like that :)
You can also go outside, walk through a park, go to your favorite coffee shop! I know that when I go out, I feel a lot better.
Another thing that helps is surrounding yourself with good people/friends/family. I miss my friends dearly and know that whenever I was with them, I was bursting with joy!
For some people, music can help a lot! I listen to stuff like My Chemical Romance whenever I'm starting to not feel so well, but that's just me.
Reach out to support groups, too. Set a healthy goal for yourself! :)

If ever you're feeling super super terribly down and feel as if there's no coming back from it, call the suicide hotline <3 1-800-273-8255