Who should I sing with on karaoke night?

Last year, my friend A and I sang at an annual karaoke night at the library. We agreed that we were gonna do it again next year together. Well anyways, it's about that time of year, in a week actually. Here's my problem, though. A couple weeks ago, I got in a fight with A, and since it looked like we weren't gonna be friends again, I told my other friend, B, that she could sing with me in the karaoke night instead. Plus do a bunch of other thing with me, and A was supposed to do. Now I'm friends with the A again, and I'm not sure what to do, or who to sing with! I mentioned a trio to B- me, A, and herself- to the other girl. But she didn't like the idea. If I go off and explain the what happened to A, she'd ask why we can't do a trio with B. Which is exactly what I want to avoid, since B didn't like the idea of singing with A in it. What do I tell her... them? Anyone's answers are appreciated! Thanks.