Don't avoid head to head contact never! Mine did the same but week after week he's getting better, now he only spooks once or twice ! Just be super cool when he spooks and try not to give too much attention in that moments.
If you have friends that have horses and a place to ride, start out slowly at a walk and have them come toward you. After many passes of not spooking, reward him. Then move the other horses closer and go to a trot, then canter. Make progressions over an appropriate timeline until he is 100% sound. Horse shows will become a breeze! :)