To be honest, I am remembering the video you posted of your first jumping session with this mare and there was some mouth bopping going on. I mean you don't have a stable jumping seat yet, so naturally, you bopped the mare in the mouth a bit there. After a bit, this too can make a horse hesitant to jump with you on it's back.
I would go back to free lunging her a bit over some jumps, and maybe you'll have a chance to get a few lesson for yourself on jumping. Jumping has a technique to it that takes time and instruction to learn. Ask anyone who jumps regularly and they will tell you how long they have worked to develop an strong seat and independent hands.
I am not trying to dis you, only to say that your horse isn't lacking respect for the jump, I think she is demonstrating self preservation skills, to be honest. Horses are really good at that.