I'll keep the story as short as I can.
I got the job right out of college at a local bank. I was a loyal, good employee and I was working for about 55h/week, a lot of unpaid overtime because it was my first job and I was dumb like that. The cost of living was high, but I was able to pay for what I needed and save as much as I could.
Fast forward to a regular Friday afternoon with a very low traffic when I started to feel off, very dizzy and something was clearly wrong. We had two thermometers in the kitchen so I used them both and they showed a fever of 103 °F (39.4 °C). I quickly told my boss about how I was feeling and asked if I could leave work early. This was the first time I ever asked to leave early. His only reaction was to tell me to suck it up. This was the last straw. It was 3pm so I had 2 more hours of trying to distract myself from reality until the end of the work day. I stayed, reluctantly, took some pills my work friend gave me and my fever got a bit lower. I managed not to faint and, to my surprise, I didn't crash my car on my 1 hour drive back to my hometown.
I had 20 paid vacation days from 2021 to roll over to 2022 because I took no days off (thanks Europe), so I registered that PTO first, handed in my resignation letter and dipped. I have no student loans and a 10 month expenses emergency fund in my savings account. Also moved back with my parents to save more money and figure things out. I don't know what I will do next but all my friends and family supported my decision. The only thing I regret is not seeing the red flags earlier (I unfortunately have many poor management stories from this job), I sacrificed my sanity for a job that could replace any of us the next day. No one lays on their death bed and says 'If only I had worked harder for my employer/company'.
Have you ever quit your jobs without having a new job lined up? If so, how did it turn out for you?