Stepfamily and out of town trips

So today my dad, little sister, stepmom, and I are leaving to go out of town 4 hours away to see my great grandma who is in the nursing home. I don’t really want to go because I don’t even know her, I’ve only seen her twice in my almost 17 years of life, but it’s family so I’m going. We are probably staying the whole weekend until Sunday, today is Friday. Anyways this isn’t the point of my post just a little backstory. A month ago I was forced to go see my stepfamily 3 hours away and I was very upset because I don’t feel like my dad respects my feelings (I posted about that on here a while ago) and now my step mom is planning a trip for next weekend for us to go 4 hours away to see her daughter and son in law so my dad and him can go shoot the cyoties (idk how to spell it😂😭) that have been killing deer up there. I already know they are going to force me to go, but I would also like to see my boyfriend as he is more important to me than my step family that constantly disrespects me and invades my privacy. How could I bring it up to my dad in a respectful way that I’m not going. I don’t think he should even have a say in this one as I’ve been compliant with all of the other trips to see her family when I clearly didn’t want to go and didn’t enjoy it. I think I should have a say in whether I want to go see people who don’t respect me and talk shit about me.