I agree with the others, it's unusual in active people.

I don't know much about it, except what I've heard from respirologist (aka pneumologist) friends about it. It usually is related to smoking, environmental/work issues (like working in an environment with an enormous amount of dust).

I strongly recommend seeing a specialist about it to confirm the diagnosis and get some education about how to manage it. I'm not certain, but nearly sure that you can at least stop the progress of COPD, if not partly reverse it.

I'm also quite certain that "quit riding" is not part of the solution...

Big hug - good luck.