Do you believe my focus to gain strength and confidence in the gym is incorrect? Is the only way to become more confident to simply do the thing that makes you doubt yourself?
There was a time when I thought "wooden swords" were bullshit. I thought the only true way to develop was to do so while confronting serious consequences. In "Assault on Lake Casitas" Brad Lewis described a friend who thought using a saw guard led to sloppy work, "Better to work without a net, without a saw guard. The intensity was greater, more concentration, total commitment, better results."
Now however, I understand there is a time and place for the safety net, that you might actually go further, beyond yourself when you have the net. As long as you are well aware that the net can just as easily keep you from going beyond because doing so isn't necessary.
In his (1979) book titled "Zen In The Martial Arts" Joe Hyams wrote,
"A dojo (practice hall) is a miniature cosmos where we make contact with ourselves - our fears, anxieties, reactions, and habits. It is an arena of confined conflict where we confront an opponent who is not an opponent but rather a partner engaged in helping us understand ourselves more fully."
I believe the dojo may be anywhere or anything, like the gym. Self-expression in the gym is the same as behavior in the outside world. Testing and self-hazing in the gym elevates or crushes us depending on whether we overcome ourselves or fall short of our expectations and self-image. For those who use the gym as a tool of self-discovery every success is the cue for analysis, and every failure produces the same reaction: what allowed me to transcend today? Or, what caused me to fall short? We can face these tests alone or with partners. Partnership in the gym is like the mountains, your partner must be a peer, for whose respect you will work hard, who you will help, who will help you, who ultimately walk the path with you.
This is a roundabout way of saying, "you need the gym or dojo to prepare but you need the real thing to test." Proper use of the gym includes repeated confrontation with tasks you are not sure you can accomplish, things you are afraid to try. Start doing those things that you avoid. Create some artificial tests that make you nervous, no matter how irrelevant to the actual task. Consistently taking those tests can take you from a point of asking "Why?" to a point of saying, "Why not?" and that might be what gets you past a particular barrier.
The gym is addictive. As long as you are using it as tool to accomplish goals outside of it then spending time and energy there is good. But if you are using it to scratch the itch that only climbing used to do, then it has become a substitute and you should examine its utility more carefully.