as someone who actually went through some 20 years of depression, with all the bells and whistles, let me attempt a slight correction of this well-intended speech:
You, yes, you,
I know how you feel. Or, at least I can imagine. I've went through the darkest of nights, just like you. I've stood in the brightest of daylight and felt no warmth; I felt alone among friends and family. Just know this: it's alright to feel the way you feel. You are not alone with it. Be kind to yourself. Allow yourself to feel sad, terrified, weak and out of control. This is all part of being alive.
And, treat yourself, with those things that you feel capable of achieving. Don't aim for finally getting fit, aim for taking a walk. Don't aim for finally figuring your life and career out, aim for a the best tomato sauce you can make.
Setting unachievable goals is a hallmark of depression. The way out of it is to set tiny, small goals and being kind to yourself if you fail them. If taking a long shower is the only thing you got done today, hey, at least you now smell better! If your homework is just too much right now, allow yourself to fuck it up or not to do it at all.
Also, consider what the worst thing that could happen actually is. If you're really affraid of getting fired from the job that you hate, maybe you should get fired. If the degree you're chasing doesn't even interest you anymore, allow yourself to not be interested.
We all make mistakes, big and small. We all are hardly in control of anything. You and me, we can learn to accept the roller coaster we're on for what it is.
If you've made it this far already, and through so much suffering - if you feel like you've had enough and are willing to end your life for it - what would be the harm in at least trying to be kind to yourself for the rest of it.
Go out with a full stomach of the best food you can get - you might find that you like the taste enough to keep going on for at least one more...