With 3 weeks until deadline, been working massive overtime and under massive pressure.
My body just gave up finally, for 5 days I've been unable to get up at all.

I feel your pain bro, unfortunately I don't know what to say in this type of situations because am in it too.

Nothing to do, sick leave, body and mind needs time to recover. Long walks and hard exercise plus proper diet and lots of rest makes me recover in about 2 weeks.

Yeah man @h3ll is right. There are lots of things I do to cope and one of them is to breathe deeply, close my eyes, and picture myself in years to come. I take Efexor for anxiety and panic attacks. Once I had my first real big attack, I told myself, "fuck this shit. Nope."

Lots of people in our respective industries are on meds to get by due to everything you just described. I make time for life. The best thing you can do is learn to be confident in yourself and know your limits. Dictate your own deadlines and if you don't hit them, shrug it off.

Know your peers and your superiors at work. If you dictate to them what you will and will not do, you'll be better off. Never get it in your head that you'll be fired for underperforming. That's just self abusive. Do your best to perform but don't over perform. The minute an employer or client grows comfortable with the fact that you'll work a 24 hour shift is the minute you just lost the upper hand. No deadline us worth detrimental health.