If you think it will make you feel better to sell this horse, then sell it and try again. However, horses will stop at jumps again with you, and you will fall off again, for this and other reasons. Accepting this, and being able to handle the knowledge is part of riding horses. If you have ongoing issues due to a fall in the past, using a protective vest is a good plan to hope to avoid re injury of healed past injuries. It’s a good plan even without this history LOL.
Rather than putting blame on the horse, and selling a good horse that may be difficult to replace, I would instead work on your riding skills, your own self confidence, and strength in your seat and legs. Understand WHY a horse stops at a jump, and THANK him for doing so, when it is done to save your own life (and his). Learn techniques for fewer stops, for coping with the problems encountered when attempting to jump successfully, and solving those problems before the horse has to refuse to jump.
The largest reason why a horse may refuse a jump is tension or fear in the rider. Sell this horse, buy another, but have the fear/tension remain in you may not solve your problem. You must truly WANT to jump the jump, and instinctively do the right things to make it happen. If fear remains in you, this does not happen. The horse picks up on these things. If the horse stops, and you are relaxed about it, and not fearful and tense, you are more likely to remain mounted through it. If you do not WANT to jump the jump, if the fear remains in you, perhaps taking up a different aspect of riding, without jumps, may be the answer for you. Good luck, I hope you can get your fear issues under control. There isn’t one of us who has not been injured in falls with horses, if we have ridden for a while. With the law of averages, some of these falls result in severe injuries. The ability to put it behind us is key to being riders in our old age. I have friend who was injured racing (a jockey). He had fallen in races, been injured many times, several surgeries etc, and was still doing the job, and no fear. But the last injury was nearly fatal, he had Princess Diana’s injury, bleeding into the pericardial cavity, and death approaching in the ambulance. The ambulance attendant saved his life, cutting into him and pulling the blood off his heart before he ever got to the hospital. He survived, though it took several years to recover. Then he was riding a young horse on MY farm, and got dumped. Horse came back without him. We went out looking for him, with some trepidation. Found him walking home, unhurt. He said, “the last time I fell off, I didn’t get up, ha ha!” So yes, it is possible to put this sort of thing behind you, if you are that sort of person.