Tamed, Name, and Saddled Horses Despawn

I'm on a survival world, I summoned a horse. I tamed that horse, saddled it, and named it. I went to my base real quick, and when I came back to get it, it was gone. I searched the whole area, and no horse. I wasn't gone more than 5 minutes. Mons have never despawned for me, and I was kinda sad to be honest.