Hopefully there's someone out there who get's something out of this, 'coz you can get up off the canvas even though at times you cannot move out of bed for days ..... no showers, very little to eat, ..... it's typical behaviour where you're suffering and you just don't see what's going to change. Get to the doctor, or emergency and get some medication ..... that should give you enough breathing space and strength to get a GP who specialises in mental illness, then onto a psych. Keep going back to both very regularly until you feel some progress, then you can have a crack at exercise etc.

Too much pressure to exercise and eat properly early on, when you just can't do it, can make things worse.

My experience only, everyone's different.

You aren't on your own, that's for sure.