I have a ? about formal too. . .
 

Our formal is coming up next week, I have a great date, I'm totally excited for it...but there's one prob:
Practically all of my sisters are taking guys from this one particular fraternity to formal and I'm not...I'm taking a pledge from another fraternity. This wouldn't be a problem except that I'm not sure what I'm going to do after formal. All my sisters are going to the fraternity house for the after-party, and they told me to bring my date too but it would just be too awkward (the fraternity guys on our campus don't exactly like other fraternity guys in their house unless it's a party...it's weird, but that's life at my school). I'm not sure what my date and I are going to do after formal, and I feel bad because I want him to have fun...but it looks like it's just going to be me and him. Any ideas?!?!

Ask your date out for coffee/drinks/ice cream/etc. Just you and him. That's what I did with my GDI boyfriend, to whom I am now married. Or, go hang out at his fraternity house. It's entirely up to you.

maybe taking him to the after party would smooth relations a bit?
But if you aren't in the mood to be greek life diplomat, then you and him should do something alone.