I don't know whether to leave my dad's job or not?

Hi everybody I have been working for my dad for just over a year now before working for him i was working for a butcher making just over minimum wage for 5 days a week and now i get half of that for 6 days and the occasional 7th when i first started it was so great and our relationship was so strong but after 6 months or so he changed he now yells at me everyday and embarasses me infront of all the staff i am constantly his punching bag for hiis stress and for the last month hes been bringing his attitude home and leaving me at home while taking the rest of the family for out dinner and so on. He is worth a few million and im strugling to stay afloat ,so i started making money on the side by doing my own thing in my own time slowly but surely this new hobby is making me alot of money but is very unstable some weeks i make a $1000 others nothing but if i want to make this any bigger i need time of work. but my dad told me today to just stop it all and that me doing my own thing is affecting my performance at work.I trully believe that he just really doesnt want me to grow and keeps promising me the business in "days to come" i dont now whether to leave as its risky ill probably break ties with my dad and my whole life will change. But i no longer fully trust that he will pass on the business.i would like to thankyou for reading all this and please lend me your advice it would be much appreciated,,im 20 by the way if thats relevent