Every family has its secrets and flaws, it's just a matter of how bad it gets.
Processing your family's unique brand of broken is a lot easier if you grow up knowing the nitty-gritty. There's a big difference between having all the messed up family stories integrated into your sense of context, and finding out something terrifying as an adult. If you've ever stumbled on a big bomb about your loved ones, then you know how disorienting and traumatizing it can feel.
One of my uncles borrowed $20,000 from my other more successful Uncle to start a business and refuses to pay his more successful brother back because he's "got so much money already". The more successful uncle refuses to sue him because that's not what family does, but they are no longer on speaking terms.
My mother told me that my dad, wasn't my real dad, drunk one night when I was 16.
That was 31 years ago. To this day his side of the family still thinks I'm his.