Horses are social animals. They want to be with their own kind. Loners are few and far between among equines. In a pinch, they’ll make do with the company of other animals if that’s the only choice. I sometimes pass this field where a flock of sheep are joined by a single horse. He has a proprietorial aire, often standing slightly apart from his sheep, as if he were a sheep-horse keeping watch over his flock.
In another area paddock, this pretty dappled draft horse has a llama for a companion.