There’s no easy way to fix relationships after they are over. In her mind, consciously or subconsciously, you aren't "the one" for her anymore. At least, not as you are right now. Really the only way to turn this around is for you to leave (in an emotional and physical sense) and come back after you’ve heightened your value.

First, you need to immediately stop the emotional facebook updates. Live in the moment. Don’t dwell on yesterday. Quickly work through your stages of grief, privately, if you must. On the outside, you need to project confidence that you will be dating hot girls in no time. After all, you are a high value guy, right? Fake it until you make it. In the meantime, there are things you can do to very quickly raise your value. 1) Go to the gym 2) Work on developing as much of a social circle / life as you can (yeah, I know it’s rough with the second shift, but do your best), 3) go on dates, hit on girls, etc. 4) use facebook to document all your new social activities (post lots of pictures, especially with cute girls).

In the meantime, don’t contact your ex. If she contacts you, then make a point to be polite and friendly, but keep her at arm’s length (for now). Sub-communicate that you are a happy person with a busy social life and a lot of options (i.e. don’t get overly emotional or needy or talk about your problems when you talk to her).

Yes, it seems a bit manipulative.. but it’s no more manipulative than makeup. Guys are attracted to physical qualities, which is why make-up works. Girls, on the other hand, are attracted to guys who display dominant/leadership qualities and add-value in social situations.

After you’ve let some time pass and you’ve developed a good social circle, that’s the time to act. By then, she’s already growing bored of the new guy (inevitable). Call her up and invite her to something really fun (ideally something you were going to do anyway). Make sure it involves your social circle. If she declines, wait a few weeks and try again. When she accepts, go out, flirt a lot in a playful way, and have a really good time. Completely ignore the fact that she has a boyfriend: don’t bring him up and don’t acknowledge her comments if she mentions him.

This is the roadmap to getting a girl back after she’s dumped you. It’s not easy, but it IS effective. I can draw you the map, but you have to be the one to follow it. Most guys don’t. Guys have too many emotions wrapped up in their decision making after a break-up to approach the issue rationally. Furthermore, Disney/Chic-flicks have brainwashed most guys into believing that the best way to handle the situation is to pour their feelings out, write letters, send ridiculous gifts, etc. That would be a big mistake.

Now, go watch the first season of Californication. It's good for developing the proper frame of mind.