All things are difficult before they are easy.
Riding is a hell of a challenge, isn't it? If it's not all the learning in the saddle, and out of the saddle, remembering tests and courses (and everything your coach tells you!) that makes it hard... then the stupid things horses do to themselves and each other will definitely hit your final nerve! But hey, every little hurdle you overcome makes it one step easier next time, sometimes we just have to remind ourselves of that.