Please don't think I'm browbeating you. I was once in your situation when I got seriously hurt by a horse (try a week in the hospital with numerous breaks and punctured lungs) and I insisted that the horse wasn't at fault...it was my fault for not being a good enough rider. I refused to listen to people who advised me to get a different horse. I had created the problem: I would fix it. I kept attempting to fix something that was so far out of my league, that it's a wonder I didn't end up back in the hospital all over again. Reality hit when the horse pushed me down and reared over me. It's like a light switched on and I said...NOW. The horse is leaving NOW. The horse I loved so much went to a rider who could cope with him and they went on to do rodeos and parades, and his issues were addressed and resolved. The day I handed his lead over to the new person, he stomped on my foot and broke two toes. It helped my grief a LOT that I became so mad I was actually glad to see him go!! I got a confidence builder because at that point it's what I needed. When he got so boring I couldn't stand it any more, I moved up to something
More challenging. What is happening with you right now is not unusual.
Even experienced horse people sometimes bite off more than they can handle.
If you can't find a trainer willing to take on you and the horse, please, please seriously consider finding a new owner for the horse. I worry about you.
I just read your posting that went up at almost the same time I wrote this. Please know that I am not mad at you. I don't think anyone on here is mad at you. We are concerned for you and for Bert.