I'm Into My Friend's BF, yikes! Options

[towntown2]

Of all relationship things for me to talk about, I never thought it would be this. Because I think I've given advice on similar topics. Nevertheless--here is my story:

Guy: C
GF and Friend: B
Best Friend and confidant: J

J, B, C, and I are all friends. We're all pretty close with each other, but I'm closest to C and J. C and B have been together for almost two years now.

Their relationship was the model relationship for a while--they were very much in love, and he was the type of boyfriend everybody wanted. The quintissential cool couple who didn't do icky lovey dovey stuff. But B could never shake off her jealous nature--she could only trust a small number of girls around C. I'm one of the very few.

Lately, they've been growing apart, or at least complacent. Both J and I noticed that they don't act as if they are as into each other as they once were. Rumors started going around that C and B are over. Even J told me that C supposedly left B because he couldn't stand seeing her jealousy-driven freak outs [emotional ones, not physical freakouts].

I'm in a club with him that meets after school twice a week. During those days, we'd spend around 10 hours together at school. C and I have become close friends. But I'm flirtatious by nature, and I flirt with him--harmlessly at first.
I tend to be very touchy with him, hugging him, jumping on him. Today, I went to tackle him and he picked me up and carried me. These are all harmless-looking things, but I'm getting the feeling that to the outsiders, it doesn't look like it.

I know I'm doing things that I shouldn't do. Even if he and I really are good friends and he's loyal to B. But I have to tell you, boys and girls of cB, I don't think I can stop even if I want to. Eeek!