For me it was definitely stress related. The shittier the job the worse it got. I realize this is not a solution for everyone but what fixed it for me was to leave North America altogether and move to a country in Europe where it doesn’t feel like companies are employee grinding machines, with sustainable work week length and hours expectations, and 6 weeks PTO a year.

OP I would seriously look into reducing stress. Maybe that means scaling down your business, or learning to say no, or getting better work and life habits... I don’t know you so I can’t specifically tell bit id look in that direction.