All these issues I mentioned throughout this troubleshooting process stemmed from my Power Supply failing. Someone recommended it so long ago but I ruled it out because it had survived multiple stress tests and never caused an issue. I came home from work the other day, wife had been using the PC and left it on, when I came home everything was black like it had gone into Sleep Mode but my GPU was flashing a red LED indicating failure due to unstable or failed power supply. Replaced my PSU the next day and haven't had any issues at all since. I upgraded from an 850W to 1000W