It is important for me to separate my experience from my daughters' experience. I don't love gymnastics. I am fearful at meets, don't watch practices, and fret about everything you said. I jump whenever the phone rings when they are at practice; afraid one of them has been injured. (I have 2 L10 teenagers). If I could travel back in time, I'm not sure I would sign them up for that pre-school tumbling class. I honestly don't know.
However, my daughters DO love gymnastics. They love competing, learning new skills, their teammates, the travel, the opportunity to get a college scholarship. They belong to a tribe of gymnasts, and their friendships are closer than any I had at their age. Their experience of being a teen is alien to me. They have been injured, and they have struggled with fears, but they have not wanted to stop. They love it.
I am not going to stop supporting them due to MY fears or lack of understanding of why they do what they do. I'm going to bun their hair and pay their fees and drive them to meets on time. And I have worked to find something for myself; cycling, knitting, etc. Theirs is theirs and mine is mine. Distraction and finding fulfillment for myself rather than being gym mom all the time.
I guess I'm trying to advise you to let your daughter own her experience as much as you can and try to find a way to be OK with it. (unless the impact on the entire family and finances are intolerable - in which case throw what I said out the window).