Girlfriend broke up with me and not doing well.

A few hours ago my girlfriend informed me that after two weeks in Japan away from me, she feels different and just can't keep things going between us. I love her, quite a bit, and this obviously shows up here far too often, but I'm looking at the fact that I have to go to sleep soon and just deal with my thoughts, and wake up tomorrow and all the days after without the one thing that has been the best part of my life for quite some time now, and having far too much difficulty in justifying it. I apologize for the diatribe, but I feel awful and don't want to wake up to tomorrow.