Doofus needs Help?!?!

[Seattle-JP]

Alright so here's the deal...(*warning might get confusing) my bestfriend is dating this chick named Stacy for like 4 months...Stacy's bestfriend, Katie has been dating Stacy's brother for like 3 years, since she was a freshman in college, and they recently broke up...Now she's been coming out with all of us to the bars and parties and things right...first off I must say that this girl is smoking I would easily give her a 9 on looks alone...and she's not stuck up like most 9's are, she is really witty and she does know that she is a bombshell...So there's a little background
Well anyways she came out with us the first time on Halloween and we all had a good time we were flirting all night and we got ridiculously drunk...anyways at the end of the night she got sick (after stating all night that she never gets sick) and passes out...When we get back to the house she walks in a passes out...I'm still awake and I get the brilliant idea to write her a drunken message (I to this day I no idea what its says on it but that the last line was "chew on that drunk ass") and leave it in her pocket before my ride leaves...
So I wake up in the morning with a vague recollection of putting something in Katie's pocket...now its still kinda early...so I think if I drive over there fast enough I could sneak it out of her pocket and no harm no foul...so I get up speed racer over to the spot...and she is already gone...because I'm dumb and forgot to set the clocks back an hour...
Fast forward two weeks--So we all go out together again and I'm trying to play it off jokingly, all smiles, and stuff (trying not to let her know that I am thoroughly embarassed). She said it wasn't too bad and she thought it was cute (which by the way is the most ambiguous word that girls use)...She's still flirting with me and what not...But I don't know if she's just a flirt, or if she's not a flirt but she is on rebound mode or if she's just looking for a friend...So I guess my question is how do I get a good measure of where she sits? Like is there any kind of situational test I could use to see how she would react or where she sits right now...I mean I barely know her but I feel like that note might have put me in the DREADED "friend" runnings....any suggestions or thoughts?? anything would help??

Also should I even continue to pursue considering the situations (My bestfriend's girlfriend's best friend who has been dating my bestfriends girlfriend's brother for over 3yrs)...??? Geez this stuff is hard!

[CircleC]

Fun story. well done.
Just stay relaxed about it. If you suspect she is rebounding, then let her. But not with you. Just keep hanging out like you have been. Patience is what you need in this situation.

[Seattle-JP]

That's kinda what my plans were but patience has never been one of my strong points, I think I'll just lay low on telling her my feeling outright and just drop subtle hints into conversation