I'm so sad to hear this.
As you've always heard: things will get better. Everything is temporary. You're young, and you have miles of life ahead of you. The things you deal with now will not be relevant to your life in the years to come.
I've struggled with depressions since I was about 14, so I know sometimes things get really difficult. You just have to be strong and find things that can help you defeat those feelings.
What helped me a lot is was finding a hobby and doing things I like. In my case, I really like to learn how to code new languages and make online commmunites—and now I've been doing it for years to keep me happy.
Seeking validation from others is never needed—you must seek validation from yourself and become someonen you are proud to be.
Things get better.
If you ever need someone to talk to when you're feeling down, please reach out to me. You deserve to be happy.