Ready to Call it

I've been avoiding you again, I'm sorry.
The anxiety hasn't stopped and I'm avoiding everything. I feel like I'm borderline existing, although I've been trying to avoid that as well.
Sleep has been difficult; I'm awake until my body can no longer function, then I sleep. I often wake up late in the afternoon and fall asleep again shortly after.
So I guess those are my two states of being currently: anxious and asleep.

For two hours yesterday I felt connected to my body and able to form coherent words. I gave a presentation with a partner that neither of us had prepared for. We managed to engage the class in discussion for much longer than expected, the professor eventually gave us full reign for the entire class period. I was offering insight, I was making jokes, smiling and laughing.
My first class of the day was cancelled so I spent about an hour of the time I would normally be in that first class, studying for my upcoming class. So I guess I had three hours of productivity.

After that I spent my evening with two ladies that make me want to do better, be better. It was really nice to spend time with friends that allow me to be just as I am. There was a shadow of self-hate and shame that cast itself over the evening though. I didn't get any studying done, which had been the plan for our time together.

So far today I've:
Missed a therapy appointment that was desperately needed
Slept late, to wake up and fall back asleep again
Fucked around on my computer in this cafe for the last forty-five minutes

At what point can I just call it? When is it a good time to give up? This is it, this is all I will ever have.

Someone end this, end me. Because I'm too cowardly to do it myself.
I'm not even supposed to be here. I'm not supposed to have lasted this long.
Yeah, I'm angry. Yeah I'm pissed that I'm still here, still doing this.
Why have you all let me drag this out? Why hasn't anyone given me a reality check, "Isabel what purpose do you have here, exactly? How much space are you taking up?"
Do me a favor. Please.