Girl you dumped got a boyfriend and now you want her back. That's all you had to say man, one sentence. You are too emotional dude. Relax with that. Either give this girl time to leave her man naturally or keep being beta and going after her. What you really need to do is find some new azz. If things are so iffy with her then you really should go out and find something you are crazy about. Not something you just want when you can't have it.
You're just having a case of "FOMO". Fear Of Missing Out. Once the next chick rolls in, you'll forget all about her. There are millions of women walking around with holes between their legs. There's nothing inherently special about this one. Don't get so hung up over her.
If she is going to come back, do you think NC will be what does it? or that I should stay NC longer then hit her up to hang out?