Explore! don't assume you are straight also gay or bi. Follow your heart and see where it leads you.

Ask the guy and ask him if you take your BFF as a plus one. A group date so to speak.

Speak up and see what happens. Mutual crushes can be fleeting, soulmates can last a lifetime.

Who are you attracted to (not platonically)? If none of them, don't invite either. And don't sweat it. These dances are way overrated.

Platonic and romantic relationships have the potential to be just as important as each other, sometimes even moreso! I know that most people think that you should prioritize your love interest over your friends, but I think that it's not a standard that's universally applicable nor realistic. (Example: if your best friend of 10 years walked out on you versus a boyfriend you've been dating for a month doing the same thing, which one do you think you'd lose more sleep over?) I personally think you should tell both of them what you want to do and see their reaction. Don't let anyone else define the relationship you share with your loved ones.