Yesterday I was saddling my 4 yr old mare in the barn (she was not tied because there are things blocking the tying ring, so I just had her standing there, which she does fine). The next thing I know, the other 5 horses that we left in the pasture come barreling out of the pasture gate and ran for freedom (more like up and down the driveway). It wasn't a big deal that they got out because I just went and got the lead mare and took her to her stall and the rest followed.
But, while they were running up and down the driveway, my mare started flipping out. She was calling to the other horses and would not stand still for anything. I have worked many months with her on ground manners, and she listened when I told her to back up or turn, but as soon as I stopped moving her, she would do it on her own. It seemed like she was more nervous than excited, which I guess is understandable because all she knew was her dam, sire (who is gelded now) and all the other horses she has spent her whole life with busted out of the pasture and went for a run and she didn't know what was going on. I had to put her in her stall while I went and brought the other horses in because she was dancing around so much I was afraid she was going to back up into something or hurt herself.
Is reacting like that something all horses will do when the rest of the herd takes off running? She does not do this when I take her away from the herd or when I ride her around them, she has her full attention on me. Is there anything I can do to break her of this or is it just one of those things that comes with time?