Ask HN: Verbally abusive employer, what do I do?

I'm currently been employed by my employer for shy of 3 years. My employer was great for the first 6 months, but after that my boss turned into a huge pain and became verbally abusive. He often belittles me, calls me stupid, no common sense, etc. in front of the entire staff team, to the point it makes me physically sick to my stomach going to work for him. His boss (CEO) is his father, so trying to resolve this is impossible. I have attempted to raise concerns privately and only been treated worse by my boss.

I have been seeking new employment for over a year with no avail, at the point of desperation that I offered to work for half market rate. I've received no offers. The market where I live is bad this year.

What are my options? I have a family, I'm the sole earner, I'm forced to work 10-12 hours a day, with verbal abuse all day. I cannot merely quit, I won't have the money to provide for my family if I do.

Location: Canada