That sounds really traumatic, so sorry.
We don't have cows any more, but when we did, we had Highlands and Blue Greys, and could only ever house the two groups separately, and in age groups. Once we did put them all in a shed together (an absolute emergency situation when we extremely badly flooded in 2008) and there were terrible fights until we could split them into their groups. It did, however, on that occassion save them from drowning, and I'm afraid we left them to it until we could be sure no sheep, and none of our neighbours, were in danger of drowning.
We used to buy them in as young heifers, as we bulled them with a Simmental and sold all the calves store, and they were tied in the byre over their first winter, made them much easier to handle, and the atmosphere in there was always lovely and calm.
When we sold the cows, one particular cow had to be destroyed in a few months of being in its new home due to agression, which was a huge shock to us, as she had never been anything but delightful here.