This happened to me too. I got off my horse once and it just vanished, but I could hear its footsteps around me. After running arond looking for it frantically, it had reappeared on a cliff that was nowhere near me when I got off the horse, but I had passed that cliff a few minutes ago. It's like the path I took held onto the horse and reset its position after I got off of it.
Oh thank you so much!
I'm sure the developers are doing their best to respond and fix the reports. There are so many to look at, and some are duplicates which makes it harder for them too.
I am aware that this issue is a duplicate of another report. Please ignore, thank you!