Whenever I play Minecraft, most of the time my game crashes. The crashes occur at random times. It hasn't always been like this and it only occurred around a week ago. To make things worse, whenever I'm on a horse, the horse disappears for the world completely. I've lost several horses and a skeleton horse so far. Even if you can't bring the horses back, I would appreciate it if you can hopefully fix the bug so it won't affect my multiplayer Minecraft world.

(The image is a screenshot of the skeleton horse that went missing)