You are not the only one, you are actually lucky. Some people go through a dramatic experience with horse where both horse and rider are traumatized. Then neither can trust the other and the longer they weight the harder it gets.
Last year I was with my horse in a very busy arena, about to leave! There were about nine horses crammed into a small indoor arena, all flighty from a long break. A green horse with a bad rider spooked at a noise from snow falling off the roof and bolted, obvioulsy making the other 8 horses bolt. My horse came crashing into me as he ran past me and knocked me to the ground(luckly I wasn't trampled. One rider was trampled and one had a concussion. My horse, being extremely fast slammed into the side of the arena and jumped out and slid into a wall. It took 30 minutes to catch all the horses and mine was last. He had a complete spaz being left alone and reared up a lot. No one helped me bring him back to his field which was far away and on the way he bolted and dragged me through the snow. He ran a km down the rode to another pasture and took 45 minutes to catch. Five months later he was "normal" again and stopped spooking. That was a year ago and only a month ago did we start trusting each other again. That's how I learned to trust a horse. I learned to understand him completely and ultimately listen to him. The most important thing to do is do something you are comfortable doing so the horse doesn't feel you being nervous. Start on the ground. Bring out your horse and let her do what she likes. Work based on respect. Always listen to her. Be confident in everything yourself or the horse will have no reason to trust you. Why would you trust someone not confident in themselves. Never thing "she might not do it" or "it won't work" have a mental thought of "it willwork, there is no other way, it just will".
Exercises:
1)(roundpen):Free lunge her at whatever pace she wants (walk, trot or canter). Talk to her while she goes around you and watch to see if she focuses on you. If she is distracted put a halter on her and lunge her with a lunge line so she doesn't get stressed by feeling alone by calling out to other horses. When she is in tune with you and the atmosphere is peaceful just stop and look down and bend your body away from her as to draw her towards you. Just wait for her to come and as soon as she does reward her with a treat. Walk around with her and when she is bent towards you and follows you, reward her. This is not a join up, it doesn't force the horse to come to you, you are inviting her. A join up gives the horse no choice but to come to you-that's force, the horse doesn't want to so he doesn't want to be with you.
2)(roundpen): you are going to confidently lead your horse into scary situations, it especially works after the first exercise. Set up a tarp at one end of the round pen and without thinking it is anything special walk over it(with horse in arena but not on lunge or lead=free). If she follows you when you do this then reward her. Then put on a halter and leadrope and walk her around the roundpen(not on tarp), and then withouth thinking anything is different just walk over the tarp. If she doesn't follow don't pull. That will make her shut her brain from work and pull back and away from you. Just stand on the tarp and wait. Every step closer she takes reward her. If walking over it was no problem then don't worry about the second long part.
3) scary stuff on the horse: If she freely walks over the tarp following you then this is the next step. Putting the tarp on her. Always draw her towards you. Start by just touching the tarp to her shoulder and then move it over onto her, keep rewarding her. If she needs to move take the tarp off and let her move in a circle around you and then when she is calm try again.
