Yeah, I always want to run away, but then you have to remember, that is only going to make your problems worse.
Try to think about the good times, put some nice music on, and lie in bed, and think about everything. I find this really helps, sometimes at night when I do this, I can go to bed at 9:00pm, and still be awake, just thinking, at 2:00am. This really helps.
Also, crying and/or screaming into your pillow, where nobody can see or hear you, can really get the anger out.
Just forget about the bad times, and think about good times. NEVER think about what you should have done, it's too late for that, always think about what you CAN do, and plan ahead, this may help you plan your life, and make the short term better, and the long term will most likely be good, but this could make it even better.