I've written up an email to my boss already, as follows:
“Hi (Boss),
Please take this email as my notice of resignation, effective immediately. I know that this is very unprofessional and I should give a longer notice, but please understand I am doing this for the sake of my health. Over the past year and a half I've worked at (job), I have had many health problems both mentally and physically, with most of them stemming from my complete lack of healthy sleep. I've realized now that I am just not suited for a third shift position. I can't adhere to a consistent sleep schedule on my days off, and I can barely sleep at all on my scheduled days. I apologize for leaving my position so abruptly. I hold no ill will towards any of you and I sincerely wish you all the best.
(My name)”
The email itself pretty much describes my reasoning as best as it can. I'm just so exhausted day in and day out, 24/7. No amount of caffeine or “sleep” (I wake up 3-4 times throughout an 8-9 hour sleep period) ever makes me feel refreshed. It's been like this for a year and a half. It's torture. Before this, I couldn't hold a second shift job for much longer than a year either. Everything just gets so stale and frustrating when you realize you're gonna be working 40 or so hours every week for the next 40-50 years. Is this really all life is? Working it all away just to make the rich richer? Is every country like this in some way or can I GTFO of the US and actually make my life seem worth something?