Life is incredibly complicated and, I hate to say it, but there are no one answer. But this is what I've gathered so far.
1: The most obvious bit, you don't want to die. You have this primal urge to carry on. That's sort of the so obvious reason lol.
2: The world does a pretty good job of telling you that if you don't do society things, all hell will break loose. If you don't work you'll be nobody, if you don't go to school you'll be stupid, if you don't clean you'll be a slob, etc. But, the fact is, people fuck up all the time and if fucking up was really as bad as society said it is, well it'd be pretty damn unsustainable. So know that it's okay to relax, take a step back, and REALLY evaluate yourself and your life. You're safe. There's no danger lurking around the corner, there's no lion currently hunting you. All that fear is fabrication. It's okay to breath, I promise. It's okay to relax. All this anxiety, the self-consciousness, this mask you have to wear all the time, the imposter syndrome, all of it is so heavy and burdensome and sometimes you look out the window and think jumping off the cliff is the only solution but what you really want is some room to breath. Give that to yourself, please, you need it. Snuggle up, maybe by a loved one, and know you're okay.
3: People love you. I know it's stupid to say because you've heard that a billion times but trust me, you really are completing people right now and, if you leave, all that goes away.
There are also people who feel very similar to what you're feeling. Maybe for different reasons, but they're hurting. And most people don't make it out alive. That's scary, I know cuz I'm there. But, for whatever reason, I can see there's purpose out there. In this vast darkness, the uncertainty of life clouded by a thick dust of depression I start to wonder how many people can survive this horror and discover these unheard of lands. That sounded overly poetic lol, I know. But think of it like a voyage. Adventures can't discover new land unless they explore the unknown, they can't fulfil their purpose in life unless they take the next step. I don't know if you're religious or what, but if you are, God put you on this path because it's difficult and SOMEBODY needs to do it. That somebody has to be you. You're a voyager, an explorer, a conqueror of the worst possible kind of monster, the human psyche. They say heroes are those who die for a cause, but you're beyond brave. Most people SEEK death if they're put in your shoes, and yet you continue to fight. The idea that if somebody was put in your shoes during the peak of your depression they'd instantly kill themselves speaks volumes on your perseverance. You have actual battle scars that you should be proud of.
4: The growth that you're capable of after surviving this treacherous journey is way more than most people. The wisdom you can carry is...well...I don't know. Nobody has made it that far. So make it out for the rest of us.