As clichéd as the sentiment is, time really does heal all wounds.
You'll start to feel better incrementally once you've found something else to direct your emotions at
It doesn't even have to be a physical release of emotions, even burying yourself in music or a video game can help. I know that's tantamount to escapism, but if it works then why question it?
People say that writing stuff down (akin to a journal) can help too. I tried to do that once, but my pen kept running out. I found my journal the other day, and the end result was quite hilarious as most of it consists of "****ing pen, stop running dry you bastard". I got about 3 half-pages (and bare in mind these are A5 pages) before giving up
Personally, this option isn't one I'd go for because I suck at talking to people and the conversations in my head never match how they turn out in reality, but what if you spoke to her? Just be totally honest with her about how she made you feel. No ulterior motive, not trying to get back at her, just plain old honest unloading. Doesn't even have to be in person, you could leave her a lengthy message on Facebook or something (which isn't a bad idea because then you have the time to think how exactly to word it instead of being put on the spot by actual conversation).