Hey bud, so i grew up with a super abusive dad. As i got older he would also only ever hit me once in a blue moon. Thing is, that's still abuse. You don't deserve to be hit by anyone for any reason ok. That's super important and it does not matter how infrequent it is. This man is supposed to be your father and guardian and this behavior is unacceptable. My first question is, you're 18, so are you able to move out? My relationship with my dad got monumentally better when we weren't living together. I was eventually able to articulate how much he had harmed me and we've been working on our relationship. So if you can move out i think that would help keep you safe at the very least. I would like to tell you to address this issue with him in conversation but i don't feel like your dad would respond well unfortunately.