Don't know what to do now, does she take me seriously?

Recently told an old highschool friend(currently mid 20s now) that I liked her back in highschool and I guess I still did. Her response was "awww, really?". She gave me her phone number and what not. I usually tried to invite her to stuff, but i got this response "im always busy but I really do want to hang around." I really dont know if shes trying to be nice, or if she is really busy. She even has a boyfriend right now(yes, i know, i look like the bad guy, but hey, im sorry, i can't help it). So now that she knows, should I continue to invite her to stuff? Would it seem annoying? Or how can I make a move from there on? It really doesnt bother me that she has a boyfriend, this guy sounds like he wont be with her much longer, so I really want to pursue this. And this is no infatuation, i hate that word, is means to like someone without cause. I am going to the movies next week with some co-workers, maybe invite her then? Any tips, on what my next move should be?