I have spent over 40 years working with horses and I have been exactly where you are. I know how demoralising it feels to try everything and still feel stuck. I know the particular sadness of a horse that looks tense when you want nothing more than for it to be well and willing.
What I have found, through decades of professional practice, ongoing classical study across multiple traditions, biomechanics training, behaviour work and a deep understanding of how equipment and environment shape everything, is that the answer is almost never the one you have been given.
There is no judgement here and no wrong starting point. Whether you are rebuilding after a setback, returning after years away, or simply carrying a quiet feeling that something is missing, I will meet you exactly where you are.