Many years ago, I heard the story of a man whose business partner did dirty. They were business partners for almost 5 years and the suddenly the business partner left with company's money. Even after several years, this man didn't recovered. He ended up sounding it as a warning to his kids never to go into business with anyone. The trust was destroyed and never recovered. This is just one of those sad stories.
On the other hand, there are many success stories of friends who went into business together and succeeded to together. If you have ever gone into business with a friend, what were your biggest concerns and how did work through it.
I think there are far fewer stories of success in businesses started by friends and family, than there are disasters where relationships have suffered great strain because of issues in the business. Business often requires a single leader to drive the direction, so if you end up with compromises or stuck with opposing views on important decisions then you might fall out. It adds a whole new dimension of extra stress and may bring out a hidden, worse, side in some people x