All I can say, is I myself have been in your situation, but with time, I've taught myself to just get back up and ride. The best thing that I tell myself is that you're putting yourself on the back of a 1,200lb animal with a mind of its own, and doing it out of free will – accidents are bound to happen at some point in time if you want to keep the sport up. Just believe in yourself that you can do it, and you will excel! The best way to face a fear is head on.
Have your trainer or adult be there with you to encourage and support you!
Just work on the ground and get your confidence back up, then you can even just sit on her. The same thing happend to me a couple of months ago :( it is all in the mind as well, just think that everything is going to go well :)
Do a lot of ground work and bonding exercises. Then when you get back on just do walk trot till you feel better about being on the horse. I had to do the same thing last year. :/
Work With your horse on the ground and Bound with the horse and Then when you have the Confidence You can Ride Your horse but Start with The walk and if you are ready then you can move up.
To have a strong communication with your horse on feet first and after you get on it