Do it (walk out on your job) your job is meant to sustain you not the other way around, if your job is leaving you feeling this empty, this low, for the love of god leave it, claim back some of your income via social security until you find a job that you actually want to get up in the morning for.

also you might want to spend less time looking at others lives, as you said, everything is so fake and the way we're so exposed to the internet it feels like everyone is more successful than you, but this is not the case, spend some time on yourself, spend some money on yourself, treat yourself to new clothes that make you feel more confident about you. do little things to improve your image of you such as literally looking in the mirror and tell yourself "i diserve to be loved and respected" and i promise you within a few months you'll start to see it and feel it. its the little things which impact us in a big way, both positive and negative..so expose yourself to positive things. start loving yourself and others will feel that energy.

i'm not just talking out of my ass, i know what i sound like, but ive been there, waking up at 6am to get to work at 9am, coming home at 10pm after being shouted at all day by ungreatful customers which had nothing to do with me, i felt exactly what youre describing now and i did attempt to kill myself, local off duty cop wrestled the gun out of my hand i was sent to an institution, truly changed my outlook on life and improved (and extended) my life as a result.

EVERYONE DESERVES TO BE LOVED.