I need advice about my dad making me uncomfortable

I’m sorry, I had no idea where to post this and figured eve could be a good community for advice from other women and parents.

My parents are recently going through a divorce and my mom is staying somewhere else so my dad is always home with my sister and I. I’m 20 and she’s 15. My dad has been having a very hard time throughout this all. He’s always been a big drinker but it’s gotten worse. He gets drunk more often rather than tipsy like he normally would. The problem with that is we always fight when he’s drunk because he turns into an asshole and is way too comfortable with my sister and I, and act like we’re his friends instead of his daughters. He also got into smoking pot because of my brother and I, and is very annoying and childish. I truly believe he turns into a 13 year old when high. He makes absolutely no sense when talking and his responses make no sense. His humor turns really uncomfortable when he’s high. For example, his jokes turn into preteen humor about genitals, sex, racism, sexism, and kinda homophobia. He acts like I’m his friend when high, and always gets too comfortable with me, says uncomfortable things, and makes me scared about him being physical with me. I have a history of sexual harassement and assault so I get very scared and paranoid very fast when someone acts as though they could assault me. I think it’s how inappropriately comfortable he gets. He’s a great dad otherwise when he’s sober and has never abused us or assaulted us. It makes me scared also because I believe that anything people say or do when under the influence is something they know they are doing and mean it or wanted to do it. They may just not have the filter or conscious to keep them selves from doing it/saying it. My sister and I are starting to resent him drinking and smoking. Not really sure what to do about this.