I'm not a woman either. But from my experience, i'de go for her, boyfriend or not. If you hook up with her, it'll give her boyfriend a reason to break up with her, then she'll be happy. I've been in this exact situation, where a girl i liked had a boyfriend who she didn't really like. So i fucked her,(dont say anything, muncheemamma) and he dumped her for cheating on him. (this happened like last week).

Second thought, maybe she doesn't even like you. Since you moved away. Maybe she DID like you, but since you left, doesn't anymore. Just a thought. Either way, get some ballz and talk to her. Its all downhill from there.