What would you do in this situation? Potentially meeting my estranged father?

Essentially, my mom abandoned me when I was 4 and I haven't seen her since. She dropped me off at a man's house. She told me that was my dad. His name is on my birth certificate. He was abusive as heck and I hate him. Turns out he isn't my biological father. I did one of those Ancestry DNA things just to learn about my ethnicity. It showed a DNA match for a possible first cousin. I ignored it but he ended up getting into contact with me. He invited me to a family party. I don't want to go mostly because it's not confirmed that these people are actually my family and I think it will be really awkward. I still don't know who would be my father if he would even be there. I'd be paranoid and awkward the whole time. I also don't want to have negative feelings towards them. I know that's kind of snobby but I don't want to not like them and feel obligated to talk to them again. I also don't want to end up liking them, having emotional connections with them, and then finding out that I am not related to them at all. That would just be very uncomfortable for me. If you could please provide some insight and maybe advice, I would appreciate that. Thank you.