A Meanie from my past resurfaces

I've been on facebook for a few months now and like it much better than MySpace, which I rarely use.  Since then I've received some random friend requests including people I knew in highschool but was never really friends with and bizarre friends-of-acquaitences looking to increase the amount of people that are facebook-friends.  For the pseudo-high school friends I have taken to just accepting the request and continuing to go on pretending they don't exist.  For the random wackos looking to add to their friend roster I've quickly chosen to "ignore" them, never thinking twice about it.   

Today, I got a friend request from one of the two girls that tormented me in middle school and made my life a living hell.  This girl was one of the reasons I had such a hard time adjusting to my new school and she was constantly picking on me.  Luckily, our middle school combined with three others when you reached highschool.  She was in a lower-track of classes, so I only saw her in homeroom (which was done alphabetically - No way to avoid someone whose last name starts with the same initial.).  I found my niche and ended up with a great set of friends.  Thankfully, my highschool experience was nothing like middleschool -- hormonal pre-teens are mean! 

Why on earth would this person think I would have any interest in "friending" her now????  Not sure if I should just "Friend" her and let bygones be bygones (I think the emotional scars have healed) or ignore her (would she think I was being bitter???).  Honestly, i just don't want to let this person into my life at all, even if it is remotely from facebook.... 

Why the heck do I care?  The whole thing is very strange.