To dream of going horseback riding means that you will enjoy pleasure at the price of your good name.
To dream of riding (or sitting on) a horse foretells a coming rise in your status. You might become more popular, win a contest, or get a promotion at work. However, if you were thrown (or fell off) the horse, you will have to cope with a rival who is out to foil your plans.
If you dreamed of having any difficulties with the horse’s saddle, pay more careful attention to your personal affairs. Some change to your current plans might work in your favor.