First you have moved the goalposts from complete disregard for oneself (ignoring the possibility of becoming ill) to “making some sacrifices”.
Then you claimed “the human mind has an incredible force to resist becoming ill”. Tell your mind that while lying in a ditch with a few broken bones after an SUV crashed into you as you were walking half asleep after working for 18 hours straight and realizing you have no insurance or even a bank account because you failed to get or hold a job in pursuit of a moonshot startup idea.
The notion that starting a business automatically requires disregarding your life and people close to you is frankly some cool-aid fueled SV fever dream that doesn’t represent reality. Those startup founders with thousands to millions of YC funding, who pay themselves enough to live comfortably (with all the healthcare, dental care, good apartment and other things that many people struggle with) in one of the world’s most expensive places, are the prime example of the opposite!
People in my situation shouldn’t go all in on some new venture unless that venture can interest the likes of YC who can provide the required safety net. Not because we are mentally unfit to do it for the wild reasons you described, but just because the circumstances aren’t right.
Running even a small business is a great way to create more value for the world, but yes, it requires some sacrifices—and if you don’t have the leeway to make those sacrifices, ruining yourself is probably the worst way to go about it.
Take it easy!