Your Turn! Or: Who's that girl?

No, no, no.  I’m not killing off any characters.  Well, not any characters that are important to our lead girl, Sarah.  Not now. (No promises for the future…)  But that girl Sarah thought was her friend back in high school?  I can’t be responsible for whatever karma decides.  

You know the girl I’m talking about.  That one that turned out to not really be a friend.  The girl that was only friends with someone because of who that someone was dating.  Remember that girl from your days in high school?  When she had the opportunity to stab someone in the back, to get what she wanted, she took it.  Friends were pawns to her.  It was all an elaborate game that she fully intended to win.

What was her name?

(Does anyone else hear Madonna singing in their head from the title of this post?  Just me?  Ok.)