Not sure what to make of this?

I have a confusing situation at my work, it is kind of lengthy to get the full story, so here goes. I work in a large company and I work in the IT department that is outsourced to a separate company. I noticed that a certain female that I assisted her with some company issues. When I first noticed her I thought of her as a normal worker that needs computer assistance. The next day she flagged my attention and waved and smiled at me from at least 10-12 feet away as I was stationary and she was walking down the hall, the following day she thanked me again for the help(it was basic issue). For the past two months she has been throwing compliments to me, caught her glancing at me in the cafeteria, and a consistent flirt during the whole two months. We have made solid eye contact multiple times in the cafeteria as well. If I do not notice her in the room, she makes sure she says hi so I do notice her. When she eats lunch she almost always sits either within earshot or eye sight of me(another clue).There are many more potential signs of interest, but I won't mention them all.If there was a jury trial based on signs of interest this would be a slam dunk conviction simple as that.

I was picking up that she is interested, so while I was helping her with a printer issue(which there was nothing wrong with the printer RED FLAG), I mentioned we should go for drinks after work sometime, she said "yeah sure".I let a week go by before formally asking her out(to gauge her body language.. She works in an open office were there are ALWAYS people around, so I send my invite via email.

Here is where is gets massively confusing. She did not reply to my invite to go out. I let three days go without mentioning anything. I sent her am email saying that if you were not interested please let me know, apologized if there was mixed signals. I reiterated that if she was not interested to just let me know, I can graciously accept a thanks, but no thanks, not interested, I am busy, etc. I have had my fair share of rejections. She does not reply to that email either. So I let a week go by thinking to myself is she not interested?, did I do something wrong?. She has not said yes or no or a maybe. Flat out ignored me. I sent another email a week later. In this email I said that I liked her and found her attractive and I only asked you out because I thought she was interested, based on my extensive evidence. I also said that since I am not getting no response I will have to assume she is not interested. I have conceited the fact that I need to move on, but this is bugging me. I need to know what I could have done differently so I know for next time. I gave her multiple opportunities to say she is not interested, if she needs more time, needs to know me more. I even threw out maybe just lunch by ourselves one day at work. And she ignored that.

She has ignored me to the point that I have nothing else to work with. But my gut tells me there is something there. The thing that does not make sense if that she was the one that initiated the flirting, compliments, and the opportunity to give me a sign that she may be interested.And the ignoring ONLY started after I asked her out.

So my question is why would she ignore me that badly considering that she was the one that initiated the contact beyond normal business? I considered maybe she is shy, but not sure shy ones initiate flirting and throwing out a bunch of signs. I have seen here several times since and I have ignored her back. I have a feeling that after several weeks she will miss my attention. Any you help figuring this out would be appreciated.