Years ago I knew a family and both the parents were overly strict with their DC, quite brutal in fact. The children would jump to the parents command immediately doing jobs they were told to do, some quite difficult for children 5 and 7.
The parents said some people said how well behaved their DC were but the school head had warned them their eldest had behavioural problems. They weren’t happy at all about the advice and said the head was wrong, as they could only see how compliant their DC were. They changed their DC’s school.
Other people in the group had seen how the DC completely ignored other adults. Once the DC were asked to move away from a newborn baby while they were tossing a ball in the middle of adults sitting in a semi circle. They just looked blankly at the adult and carried on. Even when other adults they knew well asked them to just move away a few feet, they continued to throw their ball back and forth to each other. It was odd to see, the parents weren’t there at the time and had dropped the boys off while they picked up things from a nearby shop.
Your DS hitting you on your bum appears to be following his father. Your DD has no voice just like you Chickencuddle.
Your dd has a higher chance of being in an abusive relationship and your ds, hopefully not, but his role model of the same sex is an abuser.
Never doubt yourself,. You are doing the right thing to protect your dc by leaving as soon as you are able. 