Ok wow I'm gonna try to answer this but I'm so scared of answering wrong so first of all let me say that I hope your Halloween goes awesome whichever one you choose and you get tons of candy. And sorry about your BFF! You probably already know this but just in case I want to say that doesn't necessarily mean your BFF doesn't want to be your BFF anymore or anything. Just putting that out there. Anyways, it would be pretty cool if you and your brother and crush go and lots of fun, so I don't think it hurts to ask. I mean, I guess it depends on how close you are with your crush (like you guys do spend time together sometime, as in you're not just approaching some person you barely talk to and asking, which, I wouldn't do cuz I'm rly shy but idk this is you?) and if your crush says yes. I guess you're other friends could be a backup plan, but could all of you go together maybe if she doesn't have any plans so she doesn't feel left out??? Idk. Yeah, I feel like you're pretty against 3, so you probably shouldn't do it. As for costumes, do whatever you want! I don't really think I'm the person to ask for that bc I literally wear the same costume every single year (spoiler: shiba inu!) And it'd be cool if you guys all dress up if everyone else is up for it too! But anyways, I probably don't know what I'm talking about (and yet I still like to go around giving advice to ppl...), but yeah! And Halloween is a pretty long time away (right?) so you have some time to think about it and see if stuff changes!