Short story about my specific situation at one time that may help others.
I bought my horse from a stable that seemed like a well rounded, friendly stable. After a few few weeks the alarm bells kept screaming and things weren't as I originally noted. For anyone that is trying to train their horse and are making dull progress, this is for you.
I bought a horse not for the riding experience, but instead to give my horse the best possible life. My horse gem was being used as a lesson/trail/anything goes horse at the time. After buying him I took some basic lessons and so on but the one thing I noticed was that he was very elusive when he was faced with the stable owners (previous owners).
While I finally moved him out of that stable, the time spent at that stable was strictly a bonding experience. Any training or trying to train was completely out the window. I know it's not a practical scenario for most to say OK, I'll just move my horse but if you are really eager to ride or even show and your progress is going backwards, the best thing is a change of environment.
Why environment plays such an important role in training
Learning things on any level requires a lot. Being relaxed, calm, attentive and most of all an eagerness and willingness to learn. Since I love examples, picture a kid in kindergarten that is either scared out of their mind or has other influences (another kid who is a complete enemy, teacher is mean, etc). Now move that child to another classroom and he's a different person. Receptive and willing to learn without influences.
When I moved gem I noticed a 110% change in EVERY ASPECT OF HIS PERSONALITY. If moving is not an option, try to eliminate those other influences that your horse may be faced with. Your trainer may also be sending a message that your horse does not like.
For help in regard to your current situation and for friendly advice feel free to message me.
Best wishes for you and your horse!