Who Do You Believe?
There are two sides to every story. The OP learned at an early age that their dad was out of the picture because he was an addict. That’s a legitimate reason to leave someone, if you ask us. Why stick with someone who has priorities other than you and your family, right?
But on the other hand, the OP learned from her paternal uncle that dad left because mom was abusive. At one point during their relationship, mom stabbed and ran dad over with her car. Now that you have two contradictory stories, which do you believe? Guess you gotta do more digging to uncover the truth, OP.