Horse Trainer?

Recently I was training a horse that had come to the barn for a few weeks to get her manners in line before her owner moved her to her own farm.    After almost two weeks of working with her, I had no issues; this horse was smart and knew exactly which buttons she could press. She had had a hard tough previous life and knew how to survive through thick and thin. My last day of training, I was going to take her out for a trail ride by herself. The horse was in a dithery state, and I should have seen what was to happen, but unfortunately my mind was too preoccupied on personal matters.  I was out at the mounting block, still afoot, trying to send a quick text and the horse was getting more and more dithery (don't mix texting and horses- it's a dangerous mix- read on to see why). While trying to text, I just kept reminding her to stand still and be patient (one of her weaknesses was waiting)- something we had worked on and excelled at over the past few weeks.  All of a sudden, with no warning (ok I had warning, I just wasn't using my horse sense at that particular time) the horse ran off, leaving me desperately hanging on the reins trying to stop her. I let out a squawk (which apparently was confused with the half crow of our old rooster) and the reins ripped out of my hands and off she went, galloping back to her paddock.  I could swear the horse would have given me the middle finger if she could have.  I caught her, and started to cry.  My morale was beaten to a pulp.  Boy did  I feel stupid.  Lesson learned, don't mix business with personal matters!