Hesitating

I kept bumping into my primary school mates these days.
Back then, I used to be very reserved, quiet and anti-social.
The problem is, I have an AWESOME memory! and I can even remember their full name..

And when I see them in college, I would be thinking of whether should I greet them / not.

I don't want our conversation to end up like this:

me: " hey, "(name)"! long time no see, hows life?"
old classmate: " err..have we met?"
me: "primary school mates? *awkward* *awkward*"
old classmate: " Huh? haha..u looked familiar..but sorry yea, don't rmb ur name!"
me: =.=" rrrIGHtt (he/she must be thinking :"who the heck is that psycho?")

but theres a problem if I don't greet them & they happen to rmb me!
scenario:

lets call them A.
A & I exchange glances.
I look away.
If A happen to rmb me..
A would be thinking : "wahliao, this diane sooo lan sii.."

how???? can someone please help meeeee?

-diane-
hesitating