How do you know if a girl really wants to talk to you?

I'm 23 yrs old but this is more a specific case! I used to know this girl back in highschool, around 10th-11th grade. We used to speak on AIM quite a bit, and maybe hung out once and twice back then. (both times with her best friend there). My senior year, i really didn't go to school much so i just stopped talking to her I guess. I hadn't used AIM in years until just recently and was checking through my buddy list and saw her and decided to look her up on facebook and added her(stalker? :P). She remembered me and wrote a small message saying hi. fast forward a week, i talked to her once on AIM and she was saying all this deeper stuff to me, like she feels time is running out and that she doesn't know what to, and invited me to go out with her and some friends at a bar. SO the next day I text her and say what's your plans, and eventually she says something around 9pm, but never texted me back after that. Two days later, I'm on AIM(usually just for her) and she messages me first saying ';heyyyy namehere'; '; I ended up not going out that night'; so i just said It's okay and then didn't say anything else. Fast forward 2 more nights, and I decided to message her( why am I always the first one having to message? signs) and we talk here and there about random stuff like school but not really into it, but then I told her a small story she did the lol thing, and then I went idle to do something and she signed off without really saying anything. From all this, I guess I seem like im trying to make something from nothing, but everyday I keep checking AIM to see if she's on and only sign on when shes around, like im trying to get her to like me, but I guess it's becoming a bad habit. Does she really want to talk to me?How do you know if a girl really wants to talk to you?
awwww =]

thats soo cute you like this girl . haha!

uhmm probably sh jus sees you as a friend so sh doesnt really tell you when sh's loggin'

out becuz i think that sh thinks that you understand but i reckon you shuld keep trying but

dont get your hopes up that much becuz at the end of the day its you thats going through

all this so jus follow ur heart .=] or you even might get ovr her.